My partner and I have just returned from a 3 day trip to New York and went on one of these cruises as, because of time constraints, we wanted to see as much of the island as possible - by boat, we did - and also by the bus tour which this is part of - unbelievable value for money.
Money well spent in our opinon as we got to see the Manhattan "coastline" with a very good commentary from a guy we could not remember, but who was very humorous and entertaining. A FAB way to see Manhattan, especially on a hot sunny day like we did. We went past Ellis Island and also around the Staten Island where the Statue of Liberty is - unfortunately we could not get onto Staten Island as it is still bearing the brunt of Hurricane Sandy's damage, but it was awesome to see the Lady close up !!!
This cruise lasted for 2 hours and it was fab fun and good entertainment.
I would recommend you doing this if you get the time in New York