John has listed the benefits, but if you are having trouble deciding between the FL AP and FL Seasonal, I suggest you try and estimate how many times you will go. I know that when I did this, I figured the AP would be better since the number of times I would go times the $7.00 parking made up the difference quickly. So while I don't go to often in high season (which is usually the black-out dates for Seasonal passes) I still save money since I don't pay for parking. Also, I love to play mini golf so the money saved there is helful.
Another thing to consider is when people might come to visit. I have a sister with two children and they always come in summer or spring break...both of which are black-out dates on a seasonal. If I had a seasonal, I would either need to buy a four day park pass or not go to the parks with them.
Just some things to think about.