Texas de Brazil for sure (as already stated numerous times)
Hash House A Go-Go

for fat pigs like me:
The M Resort Buffet
Bacchanal Buffet at Caesars Palace
Tides Seafood and Sushi bar at the Green Valley Ranch (not on the strip, but not as expensive as those places either

I'm a cheap ass local, so:
It's off the strip and on the other side of downtown, but Mar Y Tierra is awesome. It's a mexican seafood joint with the feel of a hole in the wall.

Table 10 at Palazzo. Get the rib-eye :)