I'm going in early Feb. and I've debated quite a bit re: flying v. driving. I've chosen to drive for the following reasons:
1. No baggage concerns - no worries over carting around luggage through airports, into shuttle vans and what not, no fretting over whether stowed luggage is lost - can just pack it in the trunk and bid adieu until check-in.
2. No layovers/no scheduling concerns - I don't have to worry about keeping my son occupied if there's any delay in boarding, nor do I have to sweat traffic to airport, parking the car and all the other stresses of air travel. I can just get in the car and drive when we're ready, stop when we need to and enjoy all the scenery of a NC-FL drive.
3. Ability to drive to parks, nearby grocers, other Orlando attractions - if you drive, you won't need to pay extra money for a rental car or wait around for shuttle buses and other modes of hotel transport. Again, you can just get in the car and drive to where you need to go.
Like other posters have mentioned, I don't recommend making the long drive while sleep deprived. I'm planning on starting out in early evening the night before check-in, stopping to stay at a roadside hotel anywhere between 12 pm and 1 am and sleeping then resuming the drive around 8 or 9 am.
Yes, at first blush, it would flying is the more convenient way to go, but when you take all into consideration I think anyone could make a strong case for driving. It certainly is a less expensive option.