Index: wp-content/themes/twentyten/style.css
===================================================================
--- wp-content/themes/twentyten/style.css	(revision 20717)
+++ wp-content/themes/twentyten/style.css	(working copy)
@@ -307,6 +307,18 @@
 	top: .5ex;
 }
 input[type="text"],
+input[type="password"],
+input[type="date"],
+input[type="datetime"],
+input[type="datetime-local"],
+input[type="email"],
+input[type="month"],
+input[type="number"],
+input[type="search"],
+input[type="tel"],
+input[type="time"],
+input[type="url"],
+input[type="week"],
 textarea {
 	background: #f9f9f9;
 	border: 1px solid #ccc;
@@ -315,6 +327,12 @@
 	-webkit-box-shadow: inset 1px 1px 1px rgba(0,0,0,0.1);
 	padding: 2px;
 }
+input[type="search"] {
+	-webkit-appearance: textfield;
+}
+input[type="search"]::-webkit-search-decoration {
+	display: none;
+}
 a:link {
 	color: #0066cc;
 }
Index: wp-content/themes/twentyeleven/style.css
===================================================================
--- wp-content/themes/twentyeleven/style.css	(revision 20717)
+++ wp-content/themes/twentyeleven/style.css	(working copy)
@@ -434,6 +434,17 @@
 /* Forms */
 input[type=text],
 input[type=password],
+input[type=date],
+input[type=datetime],
+input[type=datetime-local],
+input[type=email],
+input[type=month],
+input[type=number],
+input[type=search],
+input[type=tel],
+input[type=time],
+input[type=url],
+input[type=week],
 textarea {
 	background: #fafafa;
 	-moz-box-shadow: inset 0 1px 1px rgba(0,0,0,0.1);
@@ -443,6 +454,18 @@
 	color: #888;
 }
 input[type=text]:focus,
+input[type=password]:focus,
+input[type=date]:focus,
+input[type=datetime]:focus,
+input[type=datetime-local]:focus,
+input[type=email]:focus,
+input[type=month]:focus,
+input[type=number]:focus,
+input[type=search]:focus,
+input[type=tel]:focus,
+input[type=time]:focus,
+input[type=url]:focus,
+input[type=week]:focus,
 textarea:focus {
 	color: #373737;
 }
@@ -450,9 +473,27 @@
 	padding-left: 3px;
 	width: 98%;
 }
-input[type=text] {
+input[type=text],
+input[type=password],
+input[type=date],
+input[type=datetime],
+input[type=datetime-local],
+input[type=email],
+input[type=month],
+input[type=number],
+input[type=search],
+input[type=tel],
+input[type=time],
+input[type=url],
+input[type=week] {
 	padding: 3px;
 }
+input[type="search"] {
+	-webkit-appearance: textfield;
+}
+input[type="search"]::-webkit-search-decoration {
+	display: none;
+}
 input#s {
 	background: url(images/search.png) no-repeat 5px 6px;
 	-moz-border-radius: 2px;
@@ -2048,6 +2089,8 @@
 	width: 68.9%;
 }
 #respond input[type="text"],
+#respond input[type="email"],
+#respond input[type="url"],
 #respond textarea {
 	background: #fff;
 	border: 4px solid #eee;
@@ -2085,6 +2128,8 @@
 	z-index: 1;
 }
 #respond input[type="text"]:focus,
+#respond input[type="email"]:focus,
+#respond input[type="url"]:focus,
 #respond textarea:focus {
 	text-indent: 0;
 	z-index: 1;
@@ -2175,7 +2220,9 @@
 #respond label {
 	line-height: 2.2em;
 }
-#respond input[type=text] {
+#respond input[type=text],
+#respond input[type=email],
+#respond input[type=url] {
 	display: block;
 	height: 24px;
 	width: 75%;
@@ -2448,7 +2495,9 @@
 		top: 2.2em;
 	}
 	/* Use the available space in the smaller comment form */
-	#respond input[type="text"] {
+	#respond input[type="text"],
+	#respond input[type="email"],
+	#respond input[type="url"] {
 		width: 95%;
 	}
 	#respond .comment-form-author .required,
Index: wp-content/themes/twentyeleven/functions.php
===================================================================
--- wp-content/themes/twentyeleven/functions.php	(revision 20717)
+++ wp-content/themes/twentyeleven/functions.php	(working copy)
@@ -586,3 +586,17 @@
 }
 add_filter( 'body_class', 'twentyeleven_body_classes' );
 
+/**
+ * Changes the comment form to use HTML5 input fields for email and url.
+ *
+ * @since Twenty Eleven 1.4
+ */
+function twentyeleven_html5_comment_fields( $fields ) {
+	if( isset( $fields['email'] ) )
+		$fields['email'] = str_replace( 'type="text"', 'type="email"', $fields['email'] );
+	if( isset( $fields['url'] ) )
+		$fields['url'] = str_replace( 'type="text"', 'type="url"', $fields['url'] );
+	return $fields;
+}
+add_filter( 'comment_form_default_fields', 'twentyeleven_html5_comment_fields' );
+