One thing I really like about the idea of Facebook Connect is that I don't have to manage multiple accounts. I usually only register an account on a website if I can see myself using it semi-regularly. That said, like you mentioned, I don't like having it tied to my real name, and Facebook account, so I've never used it. So if I want access to the member's area I usually just check bugmenot.com to see if they have account info.

So I guess what I'm saying is that if you want an open id system on your site, FC would be good because it has such a large userbase. On the other hand I don't know many people that use any open id system, so integrating with FC might be a waste of time.