Terminal 1 - If you have a long wait at any of the terminals, take the AirTrain to Terminal 1 and hang out on the upper level food court. You can grab something to eat and watch the planes coming and going. This was the largest landside food court in any of the terminals. There were some charging stations in the food court and on the Arrivals Level.
Terminal 2 - The Arrivals area is very small with only a few seats and a Starbucks playing loud Jazz music. There was 1 bench on the Arrivals Level and 5 on the Departures Level. This terminal is a long uncovered walk from the AirTrain station, so dragging your luggage through rain and snow will be problematic. You will be better off going to Terminal 3 and walking to Terminal 2 from there.
Terminal 4 - Seating is limited and many people were stretched out along the window sills. The seating situation was no better on the Departures Level.
Terminal 5 - This is the cleanest and most modern of all the terminals. Loud late 70's music played (think Hall & Oates). Very cold, so bring a sweater. Many people were sitting on the floor near outlets charging their phones and laptops.
Terminal 7 - This terminal had lots of tall, high back seats with armrests. Some seats had little desks but no electrical outlets nearby. Very cold, so bring a sweater.
Terminal 8 - There was not one seat on the departures level with the exception of a roped off senior citizen/disabled seating section guarded by a security officer. On the Arrivals level there was a section of wired metal seats. The area was dark, but crowded and noisy as the seats are in tight clusters.