I don't know whether you will have to collect your luggage in Amman, but my guess is that you will not have to. The Amman airport is small and dumpy, with little to do, although it has free wireless internet. Also the duty free store is quite nice. The only restaurants in the airport are Western fast-food chains (e.g., Popeyes, Pizza Hut) and coffee shops.

Depending on how much time you have, you could go into Amman. It's about a half-hour cab ride costing JOD 17.5 (about $25). Plus you would need a visa, which costs JOD 10 ($14). There's not much to do there, either, but it's a good way to kill time and see the place if you have a few hours between flights.