Damn I actually just got back from Vegas this afternoon. Was there for the last week.
Pure is a great club all around.
Opm is very cool. Has more of a hip-hop vibe to it & the girlies are FINE.
Buy a ticket package off ebay for clubs. I paid $20 & got 8 VIP passes to about 12 different clubs & it was WELL worth it. The package was worth over $500 if you paid what the clubs are asking, but most people don't know that cab drivers get all these passes for free & then try to sell them to customers or put them up on ebay themselves. If a cab driver offers to sell you any tickets, tell him "no, that's supposed to be free" and he'll have to give them to you. Otherwise, go with what I did & search ebay for a package of tickets for a few different clubs.