I'm 27. I do have a profile, actually had it nearly 3 yrs ago. I don't really use it except to stay in touch with old friends and my little sister.
However, my band's myspace site has been an extremely effective marketing tool. We use it to sell merch, give people a preview of our tunes for booking purposes etc. We do not go around asking for friends, either.
And yeah I have absolutely nailed a bunch of chicks due to myspace. But thats all in the past.