Bought tickets the night before. Wanted the premier seats, but they were already sold out. Easy 10-15 min walk to the midtown pier from our Times Square hotel. Got there about 35 minutes before departure time of 3:30 and there was already a long line. Just before boarding boat, photographer will take your picture for sale at the end of the cruise.
It was a cool afternoon, so we sat inside on the upper deck towards the front and left. Premier seats were directly behind us so they weren't really worth the additional cost. Upper deck outdoor seats were already completely taken. Note that upon leaving the pier, the lower deck front is opened up for all, but no seats.
We enjoyed the cruise and learned a lot about NYC from the narrator. We started down the Hudson past Tribeca and Soho, over to Ellis Island and the Statue of Liberty then by Lower Manhattan and finally up the East River past the Brooklyn Bridge before turning back around. Lovely views all around. He described each of the districts, NJ, the various sights, and the bridges very well Very enjoyable and well worth the cost and time.