BIG SURPRISE - I called Marriott Rewards customer service as well to verify.
The CSR told me that it is AA that is pulling out of the relationship.
This means no more travel packages with AA. I think that is a big loss. I'll have to scramble and possibly change the airline that I use.
The list of the 7 night travel packages and the airlines that you can use for conversion Marriott points to frequent flyer miles is found here. Soon, AA will drop off this list:
http://www.marriott.com/rewards/usepoints/morepack.mi