I love going to the airport! Well, to be honest, it was much better pre-Nine-Eleven, but what wasn't? PBI flies daily inter- and intra-state with direct and non-direct routes to and from many major cities. Also has direct flights to the Bahamas.
Some carriers off the top of my head are: Delta, US Airways, Northwest Airlines, American, Continental, and Spirit. (There are more, I just can't think of them.)
PBI also conveniently has information booths scattered throughout so if you're a first time visitor you can pick up info on various attractions in and around Palm Beach County.
All major auto rental agencies are located on the ground floor by baggage claim and have shuttle services to their main offices, which are located across the street, outside the ariport.
If you find yourself "stuck" at PBI, there are plenty of gift shops and restaurants to keep you occupied. And we're not talking fast food joints (although there is a BK if you like) -- these are traditional sit down establishments like Rooney's (an Irish Pub with good food and good beer) and California Pizza Kitchen.
If you're full and just want to relax with a good book or the paper, there's a lounge in the middle of the airport with comfy chairs (as comfy as they get for having been sat on by thousands of behinds) and coffee tables. I can't remember if there are televisions here, but there are at the gates.