Seems everyone wants a piece of your Dashboard now with their plugins. Sadly, not all of them care to check the code. One of these are now causing errors. I haven't narrowed down which one is doing it yet, but it might be the new Sociable (BlogPlay) update, or one of the All In One SEO (Yoast) updates.
"PHP Warning: strpos() expects parameter 1 to be string, array given in /home/wordpress/wp-includes/rss.php on line 577"
I do have them unchecked in Screen Options, so I'm going to assume they're still active when the Dashboard loads but just not displayed?