Originally Posted by bangman

Look for CCBill Solo Sites that feature hot girls & TONS of interaction - they have pretty much hands-down the best retention. Also big video megasites that update often seem to do very well.

With that said, keep your eye out for new solo site owners launching an affiliate program.
Check out Phil-Flash, TNACash, PanchoDog and LightspeedCash. They are easily the niche leaders, and you will most likely be happy with your results.

Good luck.