The only other nonstop from DFW is on Spirit, if you trust them.
I fly from Dallas to Orlando several times a year to go to WDW. Since Southwest pulled Air Tran out effective Nov 22nd, airfare here has skyrocketed. I used to pay $158.00-$220.00 r/t. I've never paid over $220.00 for DFW-MCO airfare. In the last few months thanks to Air Tran's leaving, it's hovered around $450.00, so more than double what it usually is.
Spirit will start flying nonstop from DFW to MCO and Boston in midMarch 2012. I finally broke down last week and bought airfare through them for both my upcoming May and Sept trips. Even with all their fees, they are significantly cheaper than American, Delta, Continental, and Southwest. Even though I'm flying solo, I joined the Trial $9.00 Club for $19.95. Supposedly you can't use it until after you've booked your first flight, but if you don't pay for luggage fees when you book, you can go back in later and use the $9.00 Club discount for luggage fees on that first trip. I got my May airfare for $143.58 (plus the $19.95 for the 60 day trial $9.00 Club). I still have to go back in and pay the luggage fees, but using the $9.00 Club will be able to get $20.00 off of them. My Sept trip I got for $183.58 and that included the bag fees. American charges $25.00 each way, on top of the $450.00 airfare, so $183.58 for a nonstop on Spirit looks a whole better than the $490.00 I'd pay on American or even the $328.00 that Southwest charges with their free bag policy.
Spirit may not get the greatest reviews, but most of the bad reviews I've read are from people complaining about them charging for carry ons and seat fees. I have no problem carrying just the free personal item on and putting everything else in a checked bag. Other than Southwest, most airlines charge for checked bags and choosing your seat anyway. Even our beloved Air Tran did, so that's not a big deal. As long as you are aware of all the fees prior to booking, Spirit doesn't seem that bad.

I'm giving them a chance anyway.