I've never had NY pizza so I have no idea of Graffiti's authenticity, but i can tell you it is FAR better than any of the chains/delivery places.
The pizza is good, it's hearty if you order one with lots of toppings, and the salad is excellent. The staff is very nice. The atmosphere is that of a neighborhood restaurant. I would highly recommend.
No weird pizza-bread items like Pizza Hut/Dominoes/etc. seem to concoct. Just great pizza.
Hope this clarifies for the person who wasn't clear about the other comments.