If you stay here for any period overnight, like we did, make sure your in a chair. The Amtrakpolice come around at about 5:30 and tell everyone to get up off the floor, and its a mad dash to a seat.
For Amtrak: take the escalators under the main departure board to the downstairs area. There's screens there and easy access to the tracks so you can avoid the 'Penn Station Shuffle'
Penn Station is the major intercity train station and a major commuter rail hub in New York City. Serving 300,000 passengers a day at a rate of up to a thousand every 90 seconds, it is the busiest passenger transportation facility in the United States and by far the busiest train station in North America.