I thought I read on one of the other forums that SPG has a relationship w/ DL and Marriott w/ UA, so who knows which will prevail (although perhaps Marriott/UA since Marriott is doing the acquiring).

However, a few things come to mind:

* The merger between SPG & Marriott isn't expected to close until mid-2016 & odds are the loyalty programs won't merge until sometime in 2017.

* The airline deal w/ Marriott & UA gets renewed (so far) each year, but it's not a guarantee it will continue each year.

Cheers. Sharon