I just checked. Southwest site is saying flights open up tomorrow.
When I checked for the trip we are taking in August, I got my Airtran flight for $99 on the way down. That was the day it opened as well. But it stayed that low for weeks before it started to creep up.
It's interesting because the 3 flights I can choose from right now for December all say they are operated by Southwest..but Southwest doesn't open the schedule until tomorrow.
On a related note I have been wondering for quite some time what Southwest and Airtran are going to do in Buffalo because they were offering something like 15 flights a day between the two of them at one point and surely there isn't the need for that many flights to Orlando. I wonder if one of them will be pulled out.