Index: wp-includes/admin-bar.php
===================================================================
--- wp-includes/admin-bar.php	(revision 19415)
+++ wp-includes/admin-bar.php	(working copy)
@@ -90,8 +90,7 @@
 
 	// Add WordPress.org link
 	$wp_admin_bar->add_menu( array(
-		'parent'    => 'wp-logo',
-		'secondary' => true,
+		'parent'    => 'wp-logo-external',
 		'id'        => 'wporg',
 		'title'     => __('WordPress.org'),
 		'href'      => __('http://wordpress.org'),
@@ -99,8 +98,7 @@
 
 	// Add codex link
 	$wp_admin_bar->add_menu( array(
-		'parent'    => 'wp-logo',
-		'secondary' => true,
+		'parent'    => 'wp-logo-external',
 		'id'        => 'documentation',
 		'title'     => __('Documentation'),
 		'href'      => __('http://codex.wordpress.org'),
@@ -108,8 +106,7 @@
 
 	// Add forums link
 	$wp_admin_bar->add_menu( array(
-		'parent'    => 'wp-logo',
-		'secondary' => true,
+		'parent'    => 'wp-logo-external',
 		'id'        => 'support-forums',
 		'title'     => __('Support Forums'),
 		'href'      => __('http://wordpress.org/support/'),
@@ -117,8 +114,7 @@
 
 	// Add feedback link
 	$wp_admin_bar->add_menu( array(
-		'parent'    => 'wp-logo',
-		'secondary' => true,
+		'parent'    => 'wp-logo-external',
 		'id'        => 'feedback',
 		'title'     => __('Feedback'),
 		'href'      => __('http://wordpress.org/support/forum/requests-and-feedback'),
@@ -143,7 +139,7 @@
 
 		$wp_admin_bar->add_menu( array(
 			'id'        => 'my-account',
-			'secondary' => true,
+			'parent'    => 'top-secondary',
 			'title'     => $howdy . $avatar,
 			'href'      => $profile_url,
 			'meta'      => array(
@@ -165,7 +161,6 @@
 			'title'  => $user_info,
 			'href'   => $profile_url,
 			'meta'   => array(
-				'class' => 'user-info user-info-item',
 				'tabindex' => -1
 			),
 		) );
@@ -174,18 +169,12 @@
 			'id'     => 'edit-profile',
 			'title'  => __( 'Edit My Profile' ),
 			'href' => $profile_url,
-			'meta'   => array(
-				'class' => 'user-info-item',
-			),
 		) );
 		$wp_admin_bar->add_menu( array(
 			'parent' => 'my-account',
 			'id'     => 'logout',
 			'title'  => __( 'Log Out' ),
 			'href'   => wp_logout_url(),
-			'meta'   => array(
-				'class' => 'user-info-item',
-			),
 		) );
 	}
 }
@@ -278,6 +267,12 @@
 	if ( is_super_admin() ) {
 		$wp_admin_bar->add_menu( array(
 			'parent' => 'my-sites',
+			'id'     => 'my-sites-super-admin',
+			'group'  => true,
+		) );
+
+		$wp_admin_bar->add_menu( array(
+			'parent' => 'my-sites-super-admin',
 			'id'     => 'network-admin',
 			'title'  => __('Network Admin'),
 			'href'   => network_admin_url(),
@@ -309,7 +304,16 @@
 		) );
 	}
 
-	// Add blog links
+	// Add site links
+	$wp_admin_bar->add_menu( array(
+		'parent' => 'my-sites',
+		'id'     => 'my-sites-list',
+		'group'  => true,
+		'meta'   => array(
+			'class' => is_super_admin() ? 'ab-sub-secondary' : '',
+		),
+	) );
+
 	$blue_wp_logo_url = includes_url('images/wpmini-blue.png');
 
 	foreach ( (array) $wp_admin_bar->user->blogs as $blog ) {
@@ -321,8 +325,7 @@
 		$menu_id  = 'blog-' . $blog->userblog_id;
 
 		$wp_admin_bar->add_menu( array(
-			'parent'    => 'my-sites',
-			'secondary' => is_super_admin(),
+			'parent'    => 'my-sites-list',
 			'id'        => $menu_id,
 			'title'     => $blavatar . $blogname,
 			'href'      => get_admin_url( $blog->userblog_id ),
@@ -599,6 +602,39 @@
 }
 
 /**
+ * Add secondary menus.
+ *
+ * @since 3.3.0
+ */
+function wp_admin_bar_add_secondary_groups( $wp_admin_bar ) {
+	$wp_admin_bar->add_menu( array(
+		'id'     => 'top-secondary',
+		'group'  => true,
+		'meta'   => array(
+			'class' => 'ab-top-secondary',
+		),
+	) );
+
+	$wp_admin_bar->add_menu( array(
+		'parent' => 'wp-logo',
+		'id'     => 'wp-logo-external',
+		'group'  => true,
+		'meta'   => array(
+			'class' => 'ab-sub-secondary',
+		),
+	) );
+
+	// $wp_admin_bar->add_menu( array(
+	// 	'parent' => '',
+	// 	'id'     => '-secondary',
+	// 	'group'  => true,
+	// 	'meta'   => array(
+	// 		'class' => 'ab-sub-secondary',
+	// 	),
+	// ) );
+}
+
+/**
  * Style and scripts for the admin bar.
  *
  * @since 3.1.0
Index: wp-includes/css/admin-bar.dev.css
===================================================================
--- wp-includes/css/admin-bar.dev.css	(revision 19415)
+++ wp-includes/css/admin-bar.dev.css	(working copy)
@@ -135,8 +135,13 @@
 	margin: 0 -1px 0 0;
 }
 
+#wpadminbar .ab-sub-wrapper > .ab-submenu:first-child {
+	border-top: none;
+}
+
 #wpadminbar .ab-submenu {
 	padding: 6px 0;
+	border-top: 1px solid #dfdfdf;
 }
 
 #wpadminbar .selected .shortlink-input {
@@ -247,10 +252,8 @@
 	position: relative;
 	right: auto;
 	margin: 0;
-	border: 0;
 
 	background: #eee;
-	border-top: 1px solid #dfdfdf;
 
 	-moz-box-shadow: none;
 	-webkit-box-shadow: none;
@@ -310,52 +313,52 @@
 	min-width: 270px;
 }
 
-#wpadminbar #wp-admin-bar-my-account .user-info-item {
+#wpadminbar #wp-admin-bar-my-account-default li {
 	margin-left: 16px;
 	margin-right: 16px;
 }
 
-#wpadminbar #wp-admin-bar-my-account.with-avatar .user-info-item {
+#wpadminbar #wp-admin-bar-my-account.with-avatar #wp-admin-bar-my-account-default li {
 	margin-left: 88px;
 }
 
-#wpadminbar #wp-admin-bar-my-account .user-info-item > a {
+#wpadminbar #wp-admin-bar-my-account-default li > a {
 	padding-left: 8px;
 }
 
-#wpadminbar #wp-admin-bar-my-account .user-info {
+#wpadminbar #wp-admin-bar-user-info {
 	margin-top: 6px;
 	margin-bottom: 15px;
 	height: auto;
 	background: none;
 }
 
-#wp-admin-bar-my-account .user-info .avatar {
+#wp-admin-bar-user-info .avatar {
 	position: absolute;
 	left: -72px;
 	top: 4px;
 }
 
-#wpadminbar #wp-admin-bar-my-account .user-info a {
+#wpadminbar #wp-admin-bar-user-info a {
 	height: auto;
 }
 
-#wpadminbar #wp-admin-bar-my-account .user-info span {
+#wpadminbar #wp-admin-bar-user-info span {
 	background: none;
 	padding: 0;
 	height: 18px;
 }
 
-#wpadminbar #wp-admin-bar-my-account .user-info .display-name,
-#wpadminbar #wp-admin-bar-my-account .user-info .username {
+#wpadminbar #wp-admin-bar-user-info .display-name,
+#wpadminbar #wp-admin-bar-user-info .username {
 	text-shadow: none;
 	display: block;
 }
-#wpadminbar #wp-admin-bar-my-account .user-info .display-name {
+#wpadminbar #wp-admin-bar-user-info .display-name {
 	color: #333;
 }
 
-#wpadminbar #wp-admin-bar-my-account .user-info .username {
+#wpadminbar #wp-admin-bar-user-info .username {
 	color: #999;
 	font-size: 11px;
 }
Index: wp-includes/class-wp-admin-bar.php
===================================================================
--- wp-includes/class-wp-admin-bar.php	(revision 19415)
+++ wp-includes/class-wp-admin-bar.php	(working copy)
@@ -12,10 +12,10 @@
 			$this->proto = 'https://';
 
 		$this->user = new stdClass;
-		$this->root = new stdClass;
-		$this->root->children  = (object) array(
-			'primary'   => array(),
-			'secondary' => array(),
+		$this->root = (object) array(
+			'id'       => 'root',
+			'group'    => false,
+			'children' => array(),
 		);
 
 		if ( is_user_logged_in() ) {
@@ -77,21 +77,22 @@
 			$args = array_merge( array( 'parent' => func_get_arg(0) ), func_get_arg(2) );
 
 		// Ensure we have a valid title.
-		if ( empty( $args['title'] ) )
-			return false;
+		if ( empty( $args['id'] ) ) {
+			if ( empty( $args['title'] ) )
+				return;
 
-		if ( empty( $args['id'] ) ) {
 			_doing_it_wrong( __METHOD__, __( 'The menu ID should not be empty.' ), '3.3' );
+			// Deprecated: Generate an ID from the title.
 			$args['id'] = esc_attr( sanitize_title( trim( $args['title'] ) ) );
 		}
 
 		$defaults = array(
-			'id'        => false,
-			'title'     => false,
-			'parent'    => false,
-			'href'      => false,
-			'secondary' => false,
-			'meta'      => array(),
+			'id'     => false,
+			'title'  => false,
+			'parent' => false,
+			'href'   => false,
+			'group'  => false,
+			'meta'   => array(),
 		);
 
 		// If the node already exists, keep any data that isn't provided.
@@ -99,10 +100,7 @@
 			$defaults = (array) $this->nodes[ $args['id'] ];
 
 		$args = wp_parse_args( $args, $defaults );
-		$args['children'] = (object) array(
-			'primary'   => array(),
-			'secondary' => array(),
-		);
+		$args['children'] = array();
 
 		$this->nodes[ $args['id'] ] = (object) $args;
 	}
@@ -136,10 +134,27 @@
 				$parent = $this->nodes[ $node->parent ];
 			}
 
-			if ( $node->secondary )
-				$parent->children->secondary[] = $node;
-			else
-				$parent->children->primary[] = $node;
+
+			// Ensure that our tree is of the form "item -> group -> item -> group -> ..."
+			if ( ! $parent->group && ! $node->group ) { // Both are items.
+				// The default group is added here to allow groups that are
+				// added before standard menu items to render first.
+				if ( ! isset( $parent->children['default'] ) ) {
+					$parent->children['default'] = (object) array(
+						'id'       => "{$parent->id}-default",
+						'parent'   => $parent->id,
+						'group'    => true,
+						'children' => array(),
+					);
+				}
+				$parent = $parent->children['default'];
+			}
+
+			// Update the parent ID (it might have changed).
+			$node->parent = $parent->id;
+
+			// Add the node to the tree.
+			$parent->children[] = $node;
 		}
 
 		// Add browser classes.
@@ -159,33 +174,61 @@
 		?>
 		<div id="wpadminbar" class="<?php echo $class; ?>">
 			<div class="quicklinks">
-				<ul class="ab-top-menu"><?php
-
-					foreach ( $this->root->children->primary as $node ) {
-						$this->recursive_render( $node );
-					}
-
-				?></ul>
-				<ul class="ab-top-menu ab-top-secondary"><?php
-
-					foreach ( $this->root->children->secondary as $node ) {
-						$this->recursive_render( $node );
-					}
-
-				?></ul>
+				<?php foreach ( $this->root->children as $group ) {
+					$this->render_group( $group, 'ab-top-menu' );
+				} ?>
 			</div>
 		</div>
 
 		<?php
 	}
 
-	function recursive_render( $node ) {
-		if ( ! $node->children->primary && $node->children->secondary ) {
-			$node->children->primary = $node->children->secondary;
-			$node->children->secondary = array();
+	private function render_group( $node, $class = '' ) {
+		if ( ! $node->group )
+			return;
+
+		// Check for groups within groups.
+		$groups = array();
+		foreach ( $node->children as $child ) {
+			if ( $child->group ) {
+				$groups[] = $child;
+			} else {
+				if ( ! isset( $default ) ) {
+					// Create a default proxy item to be used in the case of nested groups.
+					$default  = (object) wp_parse_args( array( 'children' => array() ), (array) $node );
+					$groups[] = $default;
+				}
+				$default->children[] = $child;
+			}
 		}
 
-		$is_parent = (bool) $node->children->primary;
+		// If we don't have any subgroups, render the group.
+		if ( count( $groups ) === 1 ):
+
+			if ( ! empty( $node->meta['class'] ) )
+				$class .= ' ' . $node->meta['class'];
+
+			?><ul id="<?php echo esc_attr( "wp-admin-bar-{$node->id}" ); ?>" class="<?php echo esc_attr( $class ); ?>"><?php
+				foreach ( $node->children as $item ) {
+					$this->render_item( $item );
+				}
+			?></ul><?php
+
+		// Wrap the subgroups in a div and render each individual subgroup.
+		else:
+			?><div id="<?php echo esc_attr( "wp-admin-bar-{$node->id}-container" ); ?>" class="ab-group-container"><?php
+				foreach ( $groups as $group ) {
+					$this->render_group( $group, $class );
+				}
+			?></div><?php
+		endif;
+	}
+
+	private function render_item( $node ) {
+		if ( $node->group )
+			return;
+
+		$is_parent = (bool) $node->children;
 		$has_link  = (bool) $node->href;
 
 		$menuclass = $is_parent ? 'menupop' : '';
@@ -222,23 +265,9 @@
 
 			if ( $is_parent ) :
 				?><div class="ab-sub-wrapper"><?php
-
-					// Render primary submenu
-					?><ul class="ab-submenu"><?php
-					foreach ( $node->children->primary as $child_node ) {
-						$this->recursive_render( $child_node );
+					foreach ( $node->children as $group ) {
+						$this->render_group( $group, 'ab-submenu' );
 					}
-					?></ul><?php
-
-					// Render secondary submenu
-					if ( ! empty( $node->children->secondary ) ):
-						?><ul class="ab-submenu ab-sub-secondary"><?php
-						foreach ( $node->children->secondary as $child_node ) {
-							$this->recursive_render( $child_node );
-						}
-						?></ul><?php
-					endif;
-
 				?></div><?php
 			endif;
 
@@ -247,7 +276,10 @@
 
 			?>
 		</li><?php
+	}
 
+	function recursive_render( $node ) {
+		$this->render_item( $node );
 	}
 
 	function add_menus() {
@@ -271,6 +303,8 @@
 		if ( ! is_admin() )
 			add_action( 'admin_bar_menu', 'wp_admin_bar_search_menu', 100 );
 
+		add_action( 'admin_bar_menu', 'wp_admin_bar_add_secondary_groups', 200 );
+
 		do_action( 'add_admin_bar_menus' );
 	}
 }