Those of you who stop by often, know that I ran into some problems after upgrading to WordPress v1.5.1. Fortunately, I believe all of those problems have been fixed now. If you would like to have a [hopefully] bug-free installation of WordPress v1.5.1, you will need to download WordPress v1.5.1 and use revision 2612 of functions.php, revision 2612 of functions-post.php, revision 2606 of xmlrpc.php, and revision 2600 of wp-blog-header.php. These changes are working wonderfully for me. I hope they work for you just as well. Good luck!
Update: WordPress v184.108.40.206 has been released. This is a recommended update for all users.
Update: WordPress v220.127.116.11 is currently being developed. As of now, there is no estimated release date.