This place is always open and always serving the same thing, which is anything that you want to eat. The menu scales down late at night, but the choices are still crazy. I've never really been impressed with the Buffett, but everything ordered off the menu has been tasty and huge. Just keep in mind that this sister restaurant to the Cheesecake Factory is just about as healthy. So, not really.
The salmon three ways is my favorite and their cocktails are strong and huge. Oh, and if the Grand Lux at the Palazzo is too busy you can walk over to the other one at the Venetian.