You will have a good time.
I'll live you some tips. This is my town and I should go about shooting it, but I travel abroad instead. sigh, soon I wil take it home.
Anyhow here is what I would shoot/visit.
Long Island City, take the E Train from Manhattan into Queens and get off on 23rd and Ely avenue (1st stop in Queens). This used to be an all industrial area. Now starting to become a good living 'hood. You can find a factory with graffiti (Five Points) look it up. You can head to the water and go for some Panoramas. Or walk about if you have time, it has potential for some good urban shots. In Manhattan, head to Battery Park City, around ground Zero. Or take a walk on the West Side Park, between 72nd and 100th streets, upper west side, Manhattan. Then head East towards Columbus Avenue and enjoy some good eating.
Talking about the empire state building, there is a bar on the roof top of 230 fifth avenue building on or about 23rd street. This Roof Top offers some good views. Warning drinks are expensive, as is all around Manhattan. http://www.230-fifth.com/
. Also, you ca take a nice walk, and snap good pictures around the Meat Packing District between 10th and 14th st on downtown's west side. Chill out at a local bar then keep moving north.
I am sure you will do all the touristic stuff, Rockefeller Center, 42nd Street - Times Square, Central Park South.
It's safe here so don't panic, just keep your eyes open, and bring some good walking shoes. And everyone walking in Manhattan seems to own a camera of some sort, so don't be affraid to pull your stuff out. And visit B&H if you need some gear or just wnat to burn 2 hours gawking at equipment.
Enjoy