WordPress 2.8.3 upgrade bizarreness

I decided to take some time to make sure that all of our blogs and websites relying on WordPress were brought up to version 2.8.3. Everything seemed to be going well until we started testing Cathy’s blog Domestic Psychology. She can post but cannot add tags. Categories work find but clicking in the "Add new tag" tag box acts like it is disabled. She can type words in the box but the Add button does not function. Tags do not get saved to the post.

So I jump over to Reality Me to see if it exhibits the same behavior. On Reality Me, I can create a post with tags with no problem. But on the dashboard under Incoming Links, Plugins, and WordPress Development Blog, I get a fatal error:

Fatal error: Please call SimplePie_Cache::create() instead of the constructor in /home/www/htdocs/realityme_net/wp-includes/class-feed.php on line 13

I have not tested the other blogs and sites yet. For both Reality Me and Domestic Psychology, I went back and deleted almost all files with the exception of the wp-content directory, the robots.txt, and the .htaccess. I rebuilt the WordPress installation and yes cache directories were removed. WP-Cache is not used. I also repaired and optimized all database tables. Active plugins on Reality Me: Audio Player, Seesmic, ShareThis, SimpleLife, Spam Karma 2, Subscribe to Comments, WordPress.com Stats, and WordPress XHTML Validator. Active plugins on Domestic Psychology: Audio player, Get Recent Comments, Lifestream, ShareThis, Spam Karma 2, Subscribe to Comments, and WordPress.com Stats.

In typing this, I realize that the SimpleLife plugin uses SimplePie and is likely to be the root cause for the Reality Me problem.

Update: Deactivating SimpleLife fixed the Reality Me problem.

Update: Disabling all plugins on Domestic Psychology did not change the fact that Post Tags could not be added to to the post.

Update: I’ve narrowed it down to Cathy’s theme. None of the active plugins on Domesticp Psychology are causing the problem. She is using a Woo theme called irresistible. Disabling this theme fixes lets her use tags with posts again. Time to see if Woo Themes has posted a fix. Yes. irrestible 2.0.0 fixes the post tag problem.