To OpenID or not to OpenID? Is it worth it?

Question

Does OpenID improve the user experience?

Edit

Not to detract from the other comments, but I got one really good reply below that outlined 3

Answer 1

In my latest application I give the users a choice. I think if you do offer OpenID it should be optional and the fact that it's optional needs be very clear to your users. I tested my signup with "average" users and they were very hesitant to sign in with their Yahoo, Facebook, Google, or what have you.

For users that do want to use OpenID, do it right. If there is additional information that your site requires and you can pull that info in along with their authentication token then do it.