Normally I wouldn’t get excited about a point release but we found BIG issues which prevented ALL themes from being supported and issues with firefox file uploading and theme previews. All have been fixed. Hope folks upgrade ASAP! Check it out at http://wordpress.org/extend/plugins/active-preview/.
In case you missed the first release post here is the gist of what the wordpress plugin does.
The plugin provides a new preview button which creates a new window which is updated in real-time with your edits to the WordPress editor (tinyMCE or the HTML editor). Check out the video demo! I know its a little rough.
Plugin site is here http://wordpress.org/extend/plugins/active-preview/