My personal opinion is that it won't create any stampedes to our area, but it will have a very large impact over time. Walton and Bay Counties are poised for massive growth. People who exaggerate the effects of the airport are stuck in the mindset of wanting property values to double every 12 months (or at least want to sell their own property or make a few sales). The folks who downplay the effects the airport will have are too caught up in trying to burst the bubble of the exaggerators.
I believe the introduction of a "major carrier" like Southwest would really accelerate things. It might create a domino effect of major companies entering the market, as well as cruise ships, theme parks, etc. While this will probably happen anyway, the announcement of a major carrier with the massive attention and resulting press could make Bay County quite hot.