I've seen many concerts at the Nokia theater, and had a great time every time. It has most of what you can ask of a venue--a nice space, a good sound system, a cool lobby, and bathrooms that don't generate huge lines. At the general admission shows I attended, there was an open floor in front and seating in the back, and you could roam between the two--however the seats get taken up pretty quickly, so if you don't like to stand, you should get there early. For some events, folding chairs are used on the floor. One nit-pick is that if the show is a sold out one, there can be long waits for alcohol, even though there are three bars. Another is that 2,100 is an ambitious capacity for the space. It can get pretty packed even under that figure. Update 1/18/08: downgraded from 5 stars to 4 stars. Reason: Overcrowding.
Pros: Location, Sound System, Overall Design
Cons: Can feel over-crowded when at or near capacity