Users of WordPress who have recently upgraded to version 2.5.1 should double check their RSS feeds! It's taken me nearly 6 weeks to spot that my Google Reader hadn't updated with the latest entries/comments from slickhouse.com!
Knowing that plenty of comments and a handful of posts had been made after May 1st, I started looking for the cause of the problem. Initially I thought it was due to the move from my shared Linux hosting to dedicated Windows hosting (at slickhouse). However, trawling through server logs showed that slickhouse had migrated long before then.
The next step was to work out what files (if any) had changed. Unfortunately 4 things occured at the start of May - upgrading to the version 8 theme; moving MySQL to another dedicated server; updating the permalinks within the database and upgrading to WordPress 2.5.1
A few Google searches later (after exhausting the first 3 things) found that many others had experienced problems with their RSS feeds after upgrading to version 2.5.1 - a bug that to this day still appears to be un-fixed.
However, there is a solution. You need to update all links to your RSS feed from /wp-rss2.php to /feed/. For the comments, /wp-commentsrss2.php becomes /comments/feed/ - much friendlier! If you're using Feedburner (highly recommended) then you'll also need to update the URL to your feeds within your account.
Within the WordPress PHP theme code, you can call these links using:
<? php bloginfo('rss2_url'); ?> <? php bloginfo('comments_rss2_url'); ?>
This is a temporary solution until the WordPress development team come up with a fix to the bug, however many may switch to these URLs permanently for their RSS feeds, or at least until they break again. Let me know if you too have encountered empty feeds. And for those wanting to subscribe to the slickhouse.com feeds - links are in the top-right (hover your mouse over the RSS icon).