Outstanding tip, Yelpers! Found this place hiding (as described, Cosmopolitan Level 3, unmarked hall between Blue Ribbon Sushi & Jaleo). Friendly staff, good beer (they had switched to Stone IPA from the Dogfishhead that another Yelper said they used to carry; the PBR was still there). They also have wine by the glass. Ordered a custom pie for our group; it was ready in about 20 minutes.
As remarked on by others, limited seating (& ambiance) in the venue itself, but we were able to go back out by the entrance where there are pool tables, dominoes, and other games, and put some of the small tables and chairs together for a nice meal.
Pizza was hot and tasty; obviously not going to be better than the best pizza parlors of New York, but definitely solid). It was a great way to get a good meal and a nice price while still in one of the Strip's hottest hotels.