WordPress 2.5.1 was released earlier today.  It fixes some bugs and has some performance enhancements.  More importantly, it contains a very important security fix.

The security fixes affect the following files:

• wp-includes/pluggable.php
• wp-admin/includes/media.php
• wp-admin/media.php

If you’re using Subversion to maintain your WordPress installation, you should only need to login to the server, switch to the root directory of your blog and enter the following command:

svn sw http://svn.automattic.com/wordpress/tags/2.5.1/

Since WordPress 2.5.1 does contain a security fix, you should upgrade immediately.