I'm not sure if this problem came from the upgrade to RC3 or upgrading mysql.
As near as I can tell, everything about my blog is functional except the ability to Save or "Save and continue Editing" a post. When I use either of those, I lose the post. forever. like, not to be found in the database.
I just lost 3 posts before I realized I had an issue. In some additional experimentation, I can tell you I see no errors or indication that anything bad has happened.
Thoughts or suggestions?