Nothing new - it sounds like the german schuelerVZ (facebook for pupils).

I always wonder what happens to a user base of such a website once it gets older and crosses the magic line - in this example, if maximum of the user distribution gets older than 30.

Not really sure why this was downvoted - the site is legit and much better than facebook.

probably because it30.com is a squatter, and it's difficult to distinguish between the two - terrible domain-name choice there.

I wonder how they intend to monetize?