diff --git a/wp-admin/admin-ajax.php b/wp-admin/admin-ajax.php
index 5e27b81488..1fe24f7695 100644
--- a/wp-admin/admin-ajax.php
+++ b/wp-admin/admin-ajax.php
@@ -150,6 +150,9 @@ case 'add-category' : // On the Fly
 		$parent = 0;
 	$post_category = isset($_POST['post_category'])? (array) $_POST['post_category'] : array();
 	$checked_categories = array_map( 'absint', (array) $post_category );
+	$popular_ids = isset( $_POST['popular_ids'] ) ?
+			array_map( 'absint', explode( ',', $_POST['popular_ids'] ) ) :
+			false;
 
 	$x = new WP_Ajax_Response();
 	foreach ( $names as $cat_name ) {
@@ -163,7 +166,7 @@ case 'add-category' : // On the Fly
 			continue;
 		$category = get_category( $cat_id );
 		ob_start();
-			wp_category_checklist( 0, $cat_id, $checked_categories );
+			wp_category_checklist( 0, $cat_id, $checked_categories, $popular_ids );
 		$data = ob_get_contents();
 		ob_end_clean();
 		$x->add( array(
diff --git a/wp-admin/edit-form-advanced.php b/wp-admin/edit-form-advanced.php
index ca48323d4d..b44e365fda 100644
--- a/wp-admin/edit-form-advanced.php
+++ b/wp-admin/edit-form-advanced.php
@@ -260,7 +260,7 @@ function post_categories_meta_box($post) {
 
 <div id="categories-all" class="ui-tabs-panel">
 	<ul id="categorychecklist" class="list:category categorychecklist form-no-clear">
-		<?php wp_category_checklist($post->ID) ?>
+		<?php wp_category_checklist($post->ID, false, false, $popular_ids) ?>
 	</ul>
 </div>
 <?php
diff --git a/wp-admin/includes/template.php b/wp-admin/includes/template.php
index 7c750f1917..c348e7f4ab 100644
--- a/wp-admin/includes/template.php
+++ b/wp-admin/includes/template.php
@@ -148,19 +148,24 @@ class Walker_Category_Checklist extends Walker {
 	}
 }
 
-function wp_category_checklist( $post_id = 0, $descendants_and_self = 0, $selected_cats = false ) {
+function wp_category_checklist( $post_id = 0, $descendants_and_self = 0, $selected_cats = false, $popular_cats = false ) {
 	$walker = new Walker_Category_Checklist;
 	$descendants_and_self = (int) $descendants_and_self;
 
 	$args = array();
 	
-	if ( $post_id )
+	if ( is_array( $selected_cats ) )
+		$args['selected_cats'] = $selected_cats;
+	elseif ( $post_id )
 		$args['selected_cats'] = wp_get_post_categories($post_id);
 	else
 		$args['selected_cats'] = array();
-	if ( is_array( $selected_cats ) )
-		$args['selected_cats'] = $selected_cats;
-	$args['popular_cats'] = get_terms( 'category', array( 'fields' => 'ids', 'orderby' => 'count', 'order' => 'DESC', 'number' => 10, 'hierarchical' => false ) );
+
+	if ( is_array( $popular_cats ) )
+		$args['popular_cats'] = $popular_cats;
+	else
+		$args['popular_cats'] = get_terms( 'category', array( 'fields' => 'ids', 'orderby' => 'count', 'order' => 'DESC', 'number' => 10, 'hierarchical' => false ) );
+
 	if ( $descendants_and_self ) {
 		$categories = get_categories( "child_of=$descendants_and_self&hierarchical=0&hide_empty=0" );
 		$self = get_category( $descendants_and_self );
@@ -169,13 +174,22 @@ function wp_category_checklist( $post_id = 0, $descendants_and_self = 0, $select
 		$categories = get_categories('get=all');
 	}
 
-	$args = array($categories, 0, $args);
-	$output = call_user_func_array(array(&$walker, 'walk'), $args);
+	// Post process $categories rather than adding an exclude to the get_terms() query to keep the query the same across all posts (for any query cache)
+	$checked_categories = array();
+	for ( $i = 0; isset($categories[$i]); $i++ ) {
+		if ( in_array($categories[$i]->term_id, $args['selected_cats']) ) {
+			$checked_categories[] = $categories[$i];
+			unset($categories[$i]);
+		}
+	}
 
-	echo $output;
+	// Put checked cats on top
+	echo call_user_func_array(array(&$walker, 'walk'), array($checked_categories, 0, $args));
+	// Then the rest of them
+	echo call_user_func_array(array(&$walker, 'walk'), array($categories, 0, $args));
 }
 
-function wp_popular_terms_checklist( $taxonomy, $default = 0, $number = 10 ) {
+function wp_popular_terms_checklist( $taxonomy, $default = 0, $number = 10, $echo = true ) {
 	global $post_ID;
 	if ( $post_ID )
 		$checked_categories = wp_get_post_categories($post_ID);
@@ -186,6 +200,8 @@ function wp_popular_terms_checklist( $taxonomy, $default = 0, $number = 10 ) {
 	$popular_ids = array();
 	foreach ( (array) $categories as $category ) {
 		$popular_ids[] = $category->term_id;
+		if ( !$echo ) // hack for AJAX use
+			continue;
 		$id = "popular-category-$category->term_id";
 		?>
 
diff --git a/wp-admin/js/post.js b/wp-admin/js/post.js
index 99cb5c88c3..a81fc81386 100644
--- a/wp-admin/js/post.js
+++ b/wp-admin/js/post.js
@@ -120,8 +120,9 @@ jQuery(document).ready( function() {
 		jQuery('#in-category-' + id + ', #in-popular-category-' + id).attr( 'checked', c );
 		noSyncChecks = false;
 	};
+	var popularCats = jQuery('#categorychecklist-pop :checkbox').map( function() { return parseInt(jQuery(this).val(), 10); } ).get().join(',');
 	var catAddBefore = function( s ) {
-		s.data += '&' + jQuery( '#categorychecklist :checked' ).serialize();
+		s.data += '&popular_ids=' + popularCats + '&' + jQuery( '#categorychecklist :checked' ).serialize();
 		return s;
 	};
 	var catAddAfter = function( r, s ) {
@@ -151,7 +152,8 @@ jQuery(document).ready( function() {
 	} );
 	jQuery('#category-add-toggle').click( function() {
 		jQuery(this).parents('div:first').toggleClass( 'wp-hidden-children' );
-		categoryTabs.tabsClick( 1 );
+		// categoryTabs.tabs( 'select', '#categories-all' ); // this is broken (in the UI beta?)
+		categoryTabs.find( 'a[href="#categories-all"]' ).click();
 		jQuery('#newcat').focus();
 		return false;
 	} );
diff --git a/wp-includes/script-loader.php b/wp-includes/script-loader.php
index 5317c5478a..5ade668bbf 100644
--- a/wp-includes/script-loader.php
+++ b/wp-includes/script-loader.php
@@ -145,7 +145,7 @@ class WP_Scripts {
 				'save' => __('Save'),
 				'cancel' => __('Cancel'),
 			) );
-			$this->add( 'post', '/wp-admin/js/post.js', array('suggest', 'jquery-ui-tabs', 'wp-lists', 'postbox', 'slug'), '20080422' );
+			$this->add( 'post', '/wp-admin/js/post.js', array('suggest', 'jquery-ui-tabs', 'wp-lists', 'postbox', 'slug'), '20080519' );
 			$this->localize( 'post', 'postL10n', array(
 				'tagsUsed' =>  __('Tags used on this post:'),
 				'add' => attribute_escape(__('Add')),