Utherverse is what SL would look like if SL hired pro-designers, but kept the world closed. It's got more activity, and less life. Basically, for the noobs who drop in out of the sky looking for a hook up, it is a better place, because they link your profile more tightly with your rl, and the world is ready made.
Umm. Well if you are into that sort of guy, you don't need an avatar to find one. A simple three liner on Craigslist works:
"Hot 29 year old asian chick with round ass seeks sex partner for play and more. Looking forward to hearing from you!"
That will get about 300 emails in 4 hours.
The reason SL works is because anyone with a few dollars and a dream can come play and try and make it. That trap, which it is, has not yet been duplicated.