This is a great small local sushi place with great service. During the World Series of Poker, this is also the spot where most of the pros hit for late night sushi runs (because it closes at 2 am).
The fish has always been great, especially considering that you are about 6 hours from the nearest ocean.
It's a very intimate restaurant, with seating for about 6 at the sushi bar and regular seating for about 30 patrons. I never go earlier than 10pm, but I would imagine it would be busy if you went there around 8.
Some tips: The WSOP roll is my favorite. The GTR and 911 rolls are great too. If it's your first time there, you can't skip the "Happy Ending with Special Sauce"!
Check out their website for the full menu:
http://www.nakedfishlv.com/menu.html