In a sense we're already down to 3 legacy carriers: United/USAirways, Continental/Delta/Northwest, and American. The six carriers have already "merged" into 3 groupings.
How much further these groupings blend is up for discussion.
It is my belief that 3 global alliances, Star - oneworld - SkyTeam will affect the local US market as carriers submerge their identity in favor of the globally recognized brand. How long this takes is anyone's guess.
Many carriers have changed their names in the past, after a period of adjustment the new identity became the recognized one.
In a few years we may all be on here reminiscing about Delta, American, United, et al...
And at the risk of using the most over-used and annoying cliche on this forum: only time will tell.
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