I was in Vegas for the game as well and decided on the Aria, mostly because they play the broadcast sound on whatever the main game is. It's a smaller sportsbook, but the TV's are large and chairs were super comfortable.
The crowd was probably 75% Seahawks, with the other 25% split between Red Sox, Tigers, and U of Miami fans.
Great atmosphere, attentive waitstaff, comfortable seating, I'd definitely recommend it for a big game.