Westward Ho is gone...

I'd check out the Stardust, and maybe even the Hard Rock...

If you like burlesque, check out the 40 Deuce club in Mandalay Bay after 10pm (very hip space, lots of stars from Hollywood in the small crowd)...

If you like top food, there are so many choices now, but these are some of my favorites:

Aureole (Charlie Palmer restaurant), MIX (lounge & restaurant, top of building - great views) @ Mandalay
Picasso @ Bellagio, Alex @ Wynn, Bouchon @ Venetian (Thomas Keller). I ate EVERYWHERE at Wynn my last two trips there, and EVERYTHING was spectacular! Just don't let your woman go into any of the stores; this is not a place for average-joe budgets!
Sushi? The outer sushi bar @ Bellagio is INCREDIBLE - live jellyfish are the background to your chefs; sublime...

Clubs? Here is the big problem; unless you "got the juice", you aren't getting in quick anywhere! SO, if your idea is to hop, FORGET IT! Stay at the hotel where the club you want is located - you can frequently get comped on entrance by flashing your room key, and if that doesn't fly, you'll get to know the folks at the door for subsequent visits.

Final Note: the Playboy club is not open yet at the Palms - when it does, I think there will be a change of focus from "Only the Strip is cool"... It could single-handedly hurt many clubs on the Strip...