I'm on the Spock beta for the people search site that made a strong impression at the Web 2.0 Expo. First three comments get the invite; if you comment after that, I'll still keep you posted if and when they offer others.
I'm generally impressed with what you can do here for tagging people, showing relationships between others, voting on accuracy of information, and other features. It could even be a new sort of Wikipedia for celebrities, and it can also potentially give you a leg up on Six Degrees of Kevin Bacon as it develops. There are bugs right now - for instance, with trying to denote related people, and there are multiple people with the same name, it's almost impossible to know if you're selecting the right person. I also had trouble claiming my LinkedIn profile for my Spock page.
If you do get an invite, come back sometime and share your thoughts.
PS: I might be a little slow today in sending the invites, but you'll get one within 24 hours.
