Originally Posted by lhl12

I am also eager to see what happens at BOS.

AA had a big presence at BOS ten or so years ago, but cut way back when it began implementing its "Cornerstone" strategy.

When AA pulled out, the vacuum was filled by JetBlue. JetBlue now has the largest market share by far of any carrier at BOS, although a merged AA/US will be much closer. There are a number of destinations that a BOS flyer can reach only via JetBlue. None of the Big Three (Delta, United and new AA) is dominant at BOS and BOS is the largest MSA in the country (#10) that does not have a dominant hub airline. (Of course it is the northeasternmost large city in the country, so hub status may not make sense for other reasons).

Also, it will be interesting to see how the addition of the USAir Shuttle to the AA route network will affect things.

And, we are seeing an increase in international service from non-US carriers at BOS (over the past year, new service has been initiated or announced to Tokyo, Istanbul, Beijing, Panama City, and Dubai), with more supposedly in the works.

Finally, with the significant renovation of Terminal B scheduled for Spring 2014, AA and US (together with Massport) will need to figure out how/whether they can get a contiguous footprint at Terminal B, and what they might do with it.

So, lots of interesting open questions/uncertainties at BOS.