I would agree that I wouldn't consider Signature at MGM Grand a luxury hotel. It seems like more of a condo hotel. Kitchen looks lovely though. I guess when I go to Vegas, I am looking more for the Bellagio/Wynn/Skylofts type experience rather than an upscale Residence Inn (for lack of a better comparison)... Good value though ($315 for a 2 BR suite)...
Amanjunkie, if you are staying on for Robuchon, you don't have to stay at MGM Grand (although it is convenient)... I think there is too much of a dropoff from Skylofts to Signature...