The best poker rooms I have ever been to in different parts of the US would be:
Borgada Poker Room in Atlantic City, NJ
They have a pretty big, nice and clean poker room. It is well kept except I am not a big fan of their poker chips. Tons of action with a lot of different types of tournaments, some of which I have not seen anywhere else to include Vegas.
Parx Casino - Bensalem, PA
This is also a pretty large poker room with tons of action and people come from all over the New England states to go play. They have their own poker room that is in a separate building from their actual casino. Great food, great massage and just lots of fun. Low NL games 1/2 all the way up to 10/10 and even a few 25/50 NL games.
Commerce Casino - Los Angeles, CA
One of the BIGGEST poker room I have ever been into. Good food, tons of live poker games
even during the evenings on a Tuesday night.
Bicycle Casino - Los Angeles, CA
If you like the drive through LA (which is a ton of traffic) and be close to a lot of the LA lifestyles, then Bicycle is in the heart of it all. Poker room is mixed in with a lot of table games on the outer rim of the poker tables. Ton of games going and the service their is pretty amazing.
Hope all this helps. If you ever get to any of these, I would recommend going to all of them. They are fairly close to each other on both sides of the US.