Ok, So I have four Itineraries booked. I checked today and the price went down on all of them.

I called AT and they said that since I booked through Kayak, They could not give me credit back for the price drop.

Naturally I did go through Kayak to take advantage of the free seat assignment (was still available when I booked these).
The thing is that the Kayak site sends you to Airtran to do the booking.

Yet Airtran says I can't get the credit back because I booked through Kayak.

Maybe I'll fire off an e-mail to AT.