I guess I struggle a bit with the bennefits of AA/NW, particularly with their hub locations. They'll have a really large concentration of hubs in the Midwest (ORD, DTW, MSP) + DFW in the center. They seem thick in the middle, but thin on the coasts.

Sure, there's Seattle, LAX, Miami, JFK and don't forget Memphis (the first hub to be eliminated), but what will they need to trim in the midwest? And can they? AA has much invested in ORD. MSP and DTW are pure NW. To me, they should cut back at ORD, keep MSP and DTW. Beef up one of the West Coast Hubs and probably JFK (didn't they just remodel?). Then, they'll have the best coverage in the US. Maybe they'll retire the oldest planes in the fleet the NW DC-9's. I've seen a few with birthdates before mine.

CO/UA seems a better marriage, because the hubs are more strategically located with less redundancy. But then the missmatched fleet could be an issue. I'd really hate to see an expansion of SONG at the sacrifice of CO domestic flights (I like my upgrades - the few I still get!)