One of the use cases of Openid is “lightweight accounts”: submitting a URL and proving you’re the person owning/representing that url is sufficient to have an account and be active on a site.
I understand that having an actual username can be practical, especially if people want to hide their openid url, and/or want to couple several OpenID logins to their account, but it should be optional. In my case, my blog is my OpenID Url and that identifies me more than enough.
I especially loathe that I have to give an email address… I want to use RSS for notification, an email address should not be necessary. And if I want to have the option to recover my account when I lost control over my OpenID url, I’ll couple several OpenID urls to my account…
