I have never been to Foxwoods, but I can tell you this, the casinos in Vegas are hugeeeeeeeeeee! The biggest I thing is the MGM Grand it is 150000 square feet and 5500 rooms! You can find all the info on it here:
I agree that MGM is the largest single Hotel and casino resort in Vegas.
That's one destination I need to make on my next visit to Las Vegas.
I still haven't been there and keep saying I will visit MGM, but it seems my visit is side-tracked by having too much fun down by Harrah's or on the other side of the street at Caesar's Palace or Bellagio.