The Javits is actually a better place for a trade show, as it's more spacious than the Hilton.ad-tech in NYC is at the Javits Center this time.
SMX is also there next month - Search Marketing Expo - East 2009: New York City, October 5-7, 2009
They have a list of suggested hotels at Javits Directory
If anybody want to visit and be a tourist, the Intrepid is a good place to go that's nearby. I think it's at the 42nd St. pier.