speaking of NYC, remember that AA and US are facing a long-term split operation at LGA because there is likely no room at either terminal to move the combined operation.
DL has operations in 3 terminals at LGA. Remember that a move by US to the Marine Air Terminal was part of the original slot swap but got pushed aside.
Suppose that DL held onto the card of allowing US to consolidate its operations with AA in a merger that was almost certain to happen even when the slot swap was happening?
There continue to be indications that that the 717 is coming to BOS to be used on the DL Shuttle and part of the reason to do so would be to allow connections off of the three legs of the Shuttle - LGA to BOS, DCA, and ORD - using the other 200+ flights DL has at LGA. that could only work if the Shuttle and the rest of DL's LGA operation is connected and there is no way to make connections between the MAT and the other 2 DL terminals w/o clearing security and taking a Port Authority bus. DL doesn't allow connections to/from the Shuttle while US allowed it for years when they had a larger LGA operation.
Methinks that we may see a resolution to AA/US' need to consolidate operations at LGA with a move to another carrier or two at LGA which could also strengthen DL at LGA and resolve some of the slot/gate disputes.
AA/US faces the same split operation at ATL as well.
A few thoughts to chew on with your turkey - vegetarian or real.