I really enjoyed the N9NE steakhouse at the Palms! The ambiance was very trendy (more like a club setting) with a caviar/champagne bar, private dining room, and a bar/lounge. Bachelor and bachlorette parties were thrown the night I was there, so you may want to consider having a private party there. The waiter we had was very attentive. I ordered their surf and turf, and it was delicious! Many of the items on their menu could be very pricey. Also, please be wary that you should get your steaks a litlte bit more rare than you're used to. Don't try to get it well-done if you like your steaks that way. Your steak might end up being very dry.
It is one of the better steakhouses I've been to in Vegas. Go try it for yourself!