Index: wp-admin/js/revisions.js
===================================================================
--- wp-admin/js/revisions.js	(revision 24718)
+++ wp-admin/js/revisions.js	(working copy)
@@ -452,6 +452,7 @@
 		render: function() {
 			wp.Backbone.View.prototype.render.apply( this, arguments );
 
+			$('html').css( 'overflow-y', 'scroll' );
 			$('#wpbody-content .wrap').append( this.el );
 			this.updateCompareTwoMode();
 			this.renderDiff( this.model.diff() );
@@ -532,7 +533,8 @@
 			tickCount = this.model.revisions.length - 1;
 			tickWidth = 1 / tickCount;
 
-			_(tickCount).times( function(){ this.$el.append( '<div></div>' ); }, this );
+			_(tickCount - 1).times( function(){ this.$el.append( '<div></div>' ); }, this );
+
 			this.$('div').css( 'width', ( 100 * tickWidth ) + '%' );
 		}
 	});
Index: wp-admin/revision.php
===================================================================
--- wp-admin/revision.php	(revision 24718)
+++ wp-admin/revision.php	(working copy)
@@ -138,7 +138,7 @@
 			({{{ data.dateShort }}})
 	<# } #>
 	</div>
-	<div class="revisions-tooltip-arrow"></div>
+	<div class="revisions-tooltip-arrow"><span></span></div>
 </script>
 
 <script id="tmpl-revisions-checkbox" type="text/html">
@@ -160,7 +160,7 @@
 	<div id="diff-header">
 		<div id="diff-header-from" class="diff-header">
 			<div id="diff-title-from" class="diff-title">
-				<strong><?php _ex( 'From:', 'Followed by post revision info' ); ?></strong>
+				<div><strong><?php _ex( 'From:', 'Followed by post revision info' ); ?></strong></div>
 				<# if ( 'undefined' !== typeof data.from ) { #>
 					{{{ data.from.attributes.author.avatar }}} {{{ data.from.attributes.author.name }}},
 					{{{ data.from.attributes.timeAgo }}}
@@ -172,7 +172,7 @@
 
 		<div id="diff-header-to" class="diff-header">
 			<div id="diff-title-to" class="diff-title">
-				<strong><?php _ex( 'To:', 'Followed by post revision info' ); ?></strong>
+				<div><strong><?php _ex( 'To:', 'Followed by post revision info' ); ?></strong></div>
 				<# if ( 'undefined' !== typeof data.to ) { #>
 					{{{ data.to.attributes.author.avatar }}} {{{ data.to.attributes.author.name }}},
 					{{{ data.to.attributes.timeAgo }}}
Index: wp-admin/css/ie-rtl.css
===================================================================
--- wp-admin/css/ie-rtl.css	(revision 24718)
+++ wp-admin/css/ie-rtl.css	(working copy)
@@ -237,4 +237,17 @@
 .screen-reader-text {
 	right: auto;
 	text-indent: -1000em;
-}
\ No newline at end of file
+}
+
+/* Revisions */
+.revisions-tooltip img {
+	float: none;
+}
+
+.revisions-tooltip-arrow > span {
+	left: 3px;
+}
+
+.revisions-meta {
+	overflow: hidden;
+}
Index: wp-admin/css/ie.css
===================================================================
--- wp-admin/css/ie.css	(revision 24718)
+++ wp-admin/css/ie.css	(working copy)
@@ -630,3 +630,10 @@
 * html #adminmenu div.wp-menu-image {
 	height: 29px;
 }
+
+/* Revisions */
+.revisions-tooltip-arrow > span {
+	left: 25px;
+	top: -24px;
+	filter: progid:DXImageTransform.Microsoft.Matrix(SizingMethod='auto expand', M11=0.7071067811865476, M12=-0.7071067811865475, M21=0.7071067811865475, M22=0.7071067811865476); /* IE7 */
+}
Index: wp-admin/css/colors-fresh.css
===================================================================
--- wp-admin/css/colors-fresh.css	(revision 24718)
+++ wp-admin/css/colors-fresh.css	(working copy)
@@ -1380,7 +1380,7 @@
 }
 
 .revisions-tooltip,
-.revisions-tooltip-arrow:after {
+.revisions-tooltip-arrow > span {
 	border-color: #d7d7d7;
 	background-color: #fff;
 }
Index: wp-admin/css/wp-admin-rtl.css
===================================================================
--- wp-admin/css/wp-admin-rtl.css	(revision 24718)
+++ wp-admin/css/wp-admin-rtl.css	(working copy)
@@ -974,12 +974,17 @@
 	right: auto;
 	left: 0;
 	padding: 9px 0 0 9px;
+	float: left;
 }
 
 .revisions-next {
 	float: left;
 }
 
+.diff-header {
+	max-width: 100%;
+}
+
 .revisions-previous {
 	float: right;
 }
@@ -990,6 +995,7 @@
 
 .diff-title {
 	float: right;
+	text-align: right;
 }
 
 .diff-title strong {
@@ -1020,12 +1026,12 @@
 }
 
 .revisions img {
-	float: right;
+	float: none;
 	margin: 5px 0 0 5px;
 }
 
 .revisions-tooltip {
-	margin-right: -73px;
+	margin-right: -62px;
 	margin-left: 0;
 	-webkit-transition: right 15ms;
 	-moz-transition:    right 15ms;
@@ -1034,10 +1040,14 @@
 	transition:         right 15ms;
 }
 
+.ie8 .revisions-tooltip {
+	margin-right: -72px;
+}
+
 .revisions-tooltip-arrow {
 	right: 0;
 	margin-left: 0;
-	margin-right: 35px;
+	margin-right: 25px;
 }
 
 .revisions-tooltip-image {
Index: wp-admin/css/wp-admin.css
===================================================================
--- wp-admin/css/wp-admin.css	(revision 24718)
+++ wp-admin/css/wp-admin.css	(working copy)
@@ -3500,10 +3500,6 @@
 /*------------------------------------------------------------------------------
   11.2 - Post Revisions
 ------------------------------------------------------------------------------*/
-body.revision-php {
-	overflow-y: scroll; /* Force a scrollbar, so centering doesn't jump */
-}
-
 .revisions-control-frame,
 .revisions-diff-frame {
 	position: relative;
@@ -3522,14 +3518,13 @@
 
 .revisions-tickmarks {
 	position: relative;
-	margin: 0 auto 0;
+	margin: 0 auto;
 	height: 0.8em;
 	z-index: 2;
 	top: 7px;
 	width: 70%;
 	-moz-box-sizing: border-box;
 	-webkit-box-sizing: border-box;
-	-ms-box-sizing: border-box; /* ie8 only */
 	box-sizing: border-box;
 }
 
@@ -3539,17 +3534,12 @@
 	float: left;
 	z-index: 10002;
 	border-style: solid;
-	border-width: 0 0 0 1px;
+	border-width: 0 1px 0 0;
 	-moz-box-sizing: border-box;
 	-webkit-box-sizing: border-box;
-	-ms-box-sizing: border-box; /* ie8 only */
 	box-sizing: border-box;
 }
 
-.revisions-tickmarks > div:first-of-type {
-	border-left-width: 0;
-}
-
 .comparing-two-revisions .revisions-controls {
 	height: 140px;
 }
@@ -3559,6 +3549,7 @@
 	text-align: center;
 	vertical-align: middle;
 	opacity: 0;
+	filter: alpha(opacity=0);
 	margin: 0 auto;
 	width: 100%;
 	height: 32px;
@@ -3569,10 +3560,12 @@
 	-ms-transition:     opacity 0.5s;
 	-o-transition:      opacity 0.5s;
 	transition:         opacity 0.5s;
+	filter: alpha(opacity=0); /* ie8 and earlier */
 }
 
 .revisions.loading .loading-indicator {
 	opacity: 1;
+	filter: alpha(opacity=100); /* ie8 and earlier */
 }
 
 .revisions .diff {
@@ -3585,6 +3578,7 @@
 
 .revisions.loading .diff {
 	opacity: 0.5;
+	filter: alpha(opacity=50); /* ie8 and earlier */
 }
 
 .revisions-meta {
@@ -3612,7 +3606,7 @@
 
 .wp-slider {
 	width: 70%;
-	margin: 0 auto 0;
+	margin: 0 auto;
 	top: -3px;
 }
 
@@ -3707,7 +3701,7 @@
 .revisions-tooltip {
 	position: absolute;
 	bottom: 105px;
-	margin-left: -69px;
+	margin-left: -70px;
 	line-height: 28px;
 	z-index: 9999;
 	max-width: 350px;
@@ -3744,7 +3738,7 @@
 	z-index: 10000;
 }
 
-.revisions-tooltip-arrow:after {
+.revisions-tooltip-arrow > span {
 	content: "";
 	position: absolute;
 	left: 20px;
@@ -3758,8 +3752,14 @@
 	tranform: rotate(45deg);
 }
 
+.ie8 .revisions-tooltip-arrow > span {
+	left: 14px;
+	top: -25px;
+	-ms-filter: "progid:DXImageTransform.Microsoft.Matrix(SizingMethod='auto expand', M11=0.7071067811865476, M12=-0.7071067811865475, M21=0.7071067811865475, M22=0.7071067811865476)"; /* IE8 */
+}
+
 .revisions-tooltip,
-.revisions-tooltip-arrow:after {
+.revisions-tooltip-arrow > span {
 	border-width: 1px;
 	border-style: solid;
 }
Index: wp-admin/css/colors-classic.css
===================================================================
--- wp-admin/css/colors-classic.css	(revision 24718)
+++ wp-admin/css/colors-classic.css	(working copy)
@@ -1486,7 +1486,7 @@
 }
 
 .revisions-tooltip,
-.revisions-tooltip-arrow:after {
+.revisions-tooltip-arrow > span {
 	border-color: #d1e5ee;
 	background-color: #fff;
 }