OpenID plugin was working great in 2.9. I probably wouldn't have noticed anything was wrong since existing OpenIDs still work fine in 3.0 as well, but a (potential) new user brought to my attention that *new* OpenIDs that the site hasn't seen before throws:
Catchable fatal error: Object of class WP_Error could not be converted to string in (path to)/in8sworld.net/blog/wp-includes/formatting.php on line 2772
it appears to be related to the creation of a new user - since thats what happens when someone new tries to log in with an OpenID, right? I've seen others complaining on other forums but not sure if maybe the problem is in the WordPress 3.0 core code?