Index: wp-admin/includes/class-wp-ms-themes-list-table.php
===================================================================
--- wp-admin/includes/class-wp-ms-themes-list-table.php	(revision 23244)
+++ wp-admin/includes/class-wp-ms-themes-list-table.php	(working copy)
@@ -331,7 +331,7 @@
 					$theme_meta[] = sprintf( __( 'By %s' ), $theme->display('Author') );
 
 					if ( $theme->get('ThemeURI') )
-						$theme_meta[] = '<a href="' . $theme->display('ThemeURI') . '" title="' . esc_attr__( 'Visit theme homepage' ) . '">' . __( 'Visit Theme Site' ) . '</a>';
+						$theme_meta[] = '<a href="' . $theme->display('ThemeURI') . '" title="' . esc_attr__( 'Visit theme homepage' ) . '" target="_blank">' . __( 'Visit Theme Site' ) . '</a>';
 
 					$theme_meta = apply_filters( 'theme_row_meta', $theme_meta, $stylesheet, $theme, $status );
 					echo implode( ' | ', $theme_meta );
Index: wp-admin/includes/class-wp-plugins-list-table.php
===================================================================
--- wp-admin/includes/class-wp-plugins-list-table.php	(revision 23244)
+++ wp-admin/includes/class-wp-plugins-list-table.php	(working copy)
@@ -411,11 +411,11 @@
 					if ( !empty( $plugin_data['Author'] ) ) {
 						$author = $plugin_data['Author'];
 						if ( !empty( $plugin_data['AuthorURI'] ) )
-							$author = '<a href="' . $plugin_data['AuthorURI'] . '" title="' . esc_attr__( 'Visit author homepage' ) . '">' . $plugin_data['Author'] . '</a>';
+							$author = '<a href="' . $plugin_data['AuthorURI'] . '" title="' . esc_attr__( 'Visit author homepage' ) . '" target="_blank">' . $plugin_data['Author'] . '</a>';
 						$plugin_meta[] = sprintf( __( 'By %s' ), $author );
 					}
 					if ( ! empty( $plugin_data['PluginURI'] ) )
-						$plugin_meta[] = '<a href="' . $plugin_data['PluginURI'] . '" title="' . esc_attr__( 'Visit plugin site' ) . '">' . __( 'Visit plugin site' ) . '</a>';
+						$plugin_meta[] = '<a href="' . $plugin_data['PluginURI'] . '" title="' . esc_attr__( 'Visit plugin site' ) . '" target="_blank">' . __( 'Visit plugin site' ) . '</a>';
 
 					$plugin_meta = apply_filters( 'plugin_row_meta', $plugin_meta, $plugin_file, $plugin_data, $status );
 					echo implode( ' | ', $plugin_meta );
Index: wp-admin/includes/plugin.php
===================================================================
--- wp-admin/includes/plugin.php	(revision 23244)
+++ wp-admin/includes/plugin.php	(working copy)
@@ -157,10 +157,10 @@
 	// Apply markup
 	if ( $markup ) {
 		if ( $plugin_data['PluginURI'] && $plugin_data['Name'] )
-			$plugin_data['Title'] = '<a href="' . $plugin_data['PluginURI'] . '" title="' . esc_attr__( 'Visit plugin homepage' ) . '">' . $plugin_data['Name'] . '</a>';
+			$plugin_data['Title'] = '<a href="' . $plugin_data['PluginURI'] . '" title="' . esc_attr__( 'Visit plugin homepage' ) . '" target="_blank">' . $plugin_data['Name'] . '</a>';
 
 		if ( $plugin_data['AuthorURI'] && $plugin_data['Author'] )
-			$plugin_data['Author'] = '<a href="' . $plugin_data['AuthorURI'] . '" title="' . esc_attr__( 'Visit author homepage' ) . '">' . $plugin_data['Author'] . '</a>';
+			$plugin_data['Author'] = '<a href="' . $plugin_data['AuthorURI'] . '" title="' . esc_attr__( 'Visit author homepage' ) . '" target="_blank">' . $plugin_data['Author'] . '</a>';
 
 		$plugin_data['Description'] = wptexturize( $plugin_data['Description'] );
 
Index: wp-includes/class-wp-theme.php
===================================================================
--- wp-includes/class-wp-theme.php	(revision 23244)
+++ wp-includes/class-wp-theme.php	(working copy)
@@ -651,7 +651,7 @@
 					static $attr = null;
 					if ( ! isset( $attr ) )
 						$attr = esc_attr__( 'Visit author homepage' );
-					$value = sprintf( '<a href="%1$s" title="%2$s">%3$s</a>', $this->display( 'AuthorURI', true, $translate ), $attr, $value );
+					$value = sprintf( '<a href="%1$s" title="%2$s" target="_blank">%3$s</a>', $this->display( 'AuthorURI', true, $translate ), $attr, $value );
 				} elseif ( ! $value ) {
 					$value = __( 'Anonymous' );
 				}