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

I feel it depends on the end users of your system. Open ID is successful in SO because people who are using SO knows some thing about Open ID.

But, I am not sure whether the same thing will be applicable to a Greeting card site / online shopping site where my parents go. The problem I see here is you give users a choice between various providers they will get confused.

One of the way I could think of for check out process is not to force a user signup. If they decide to simply check out let them do so.