Blog Types Not Saving

I'm sorry I can't give you more to go on. This is so weird. Blog Types has been working great for a long time for us. It hasn't been saving for a while now (maybe two weeks) though I didn't catch it until now. When you select the types and click "Save" everything appears normal and it even comes back with the "Settings Saved" update. BUT the data is not actually in the database.

WP 3.1.2
Blog Types 2.0.5 (I don't think 2.0.4 worked either) though it worked before that.
Oddly enough however 2.0.5 is working ok on a different installation with pretty much identical data / plugins / versions.

If I add rows manually to wp_blog_types table they will get deleted when I save Blog Types in the dashboard which tells me the global $value is 0.

Same behavior in FF and Chrome.

I know I'm probably missing something silly here. Any help would be hugely appreciated! Thanks!