The day the Southwest-Airtran merger was announced in Sept. 2010 was a dark day for Savannah travelers.

First, the merger was a serious blow to Savannah’s chances at landing a discount carrier. Airtran had already pulled out of the local airport, and Southwest had resisted because the airline already ran flights out of Jacksonville and Charleston.

Two, the merger meant less competition among discount carriers, which meant we’d gradually see them abandon their no fee approach.

Southwest on Wednesday announced it will begin selling priority boarding passes on its flights. For $40, travelers will now be allowed to join business travelers and rewards members in boarding early. This is a major change for the airline known for its general admission seating process.

How long now before Southwest abolishes its “bags fly free” policy? Or abandons its “no change fee” approach?

Those would be much more drastic changes, of course. Those two policies are cornerstones of Southwest’s marketing efforts. But Southwest is already the most popular domestic carrier, and as its market share grows, so does its leverage.

So don’t be surprised if Southwest eventually starts sticking it to customers the same way the legacy carriers do. Let’s hope that largesse opens the door to new discount carriers. The more JetBlues, the better.

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