SomeDude,
From past experience of folks on here & from my friends, phone calls to references "generally" are called in as little as just a few days after the interview to a couple of weeks after the interview....generally though I would say that when someone does well enough in the interview to generate "call references" the timeframe is 3-10 days for 80% of the folks.
Good luck...hope it all works out. I have known of folks who have slipped past this general rule due to variables but these are rate....be patient & keep all irons in the fire & if it doesn't work out this time realize that something about you generated some interest from Southwest & if you wish to apply again those characteristics will stil be there (& hopefully more) to get another call....thanks for your interest in Southwest & enjoy the family & friends at Thanksgiving!!!