I'm riding a road bike right now, and do about 20-30 miles a day. If the roads in NYC are anything like in Detroit you should probably get something with big tires, I'm thinking of getting a cyclocross bike, but haven't tried it yet.

+1 on saving about 300 for accessories, rear blinky 10, headlight 25, rear rack 40, rear panniers 40, helmet 30, portable repair kit 20, and all sorts of other things that just seem to pop up.