We just returned from Vegas and had a great time! It was our first visit. We stayed at Aladdin and it was very nice and the customer service was excellent. I did not like being hounded by the time share people but they seemed to be in every hotel lobby.
The smoke was bad, in every casino to me. I couldn't wait to get home and wash all my clothes.
We visited almost all of the hotels on the strip. IMO the best: Venetian, Bellagio, Caesar's Palace, Paris, NYNY, Aladdin. 2nd Tier would be Luxor and Mandalay Bay. I did not like the Mirage. I think it was built in the 80's... it shows. Excalibur was awful.
I can't wait to go back!