For those of you who have an IP-based virtual server running on Apache 2.x, the WordPress team has recommended that you immediately upgrade to WordPress 2.6.5, or at least upgrade the wp-includes/feed.php and wp-includes/version.php files.
Other changes mentioned:
2.6.5 contains three other small fixes in addition to the XSS fix. The first prevents accidentally saving post meta information to a revision. The second prevents XML-RPC from fetching incorrect post types. The third adds some user ID sanitization during bulk delete requests. For a list of changed files, consult the full changeset between 2.6.3 and 2.6.5.
Oh, and in case anyone else noticed, it looks like they skipped releasing WordPress 2.6.4 completely. I assume this is due to the fake WordPress 2.6.4 release, which was released by someone pretending to be the WordPress team and contained a trojan horse virus. Smart move as this should help avoid confusion.
Kyle Eslick
Kyle Eslick is WordPress enthusiast who took his passion for WordPress to the next level back in 2007 by launching WPHacks.com as a place to share hacks and review WordPress-related products. You can learn more about him by following his personal tweets here.
I am looking forward to using the ScribeSEO tool with my wordpress site. Thanks. 
Thanks a Lot. It was really very helpful for me :) 
How to make the posts section of the WP static? 
reaally excelent job. thanks 
Thanks I have been trying to figure this out for awhile now. I knew it wasn't that hard I ...
Thanks for your effort. Nice work. Keep posting such thing. 
Hi and thanks for the post, I was browsing your site when I saw your post. I have already updated to the new version.
woohoo yet another updte and 2.7 is only around the corner.