Marriott International announced today their intention to acquire Starwood Hotels and Resorts. If the deal goes through it would create the world's largest hotel company, controlling over 1.1 million rooms.
Starwood currently has an affiliation with the Caesars Entertainment properties on the Strip, and recently signed a deal to convert one of the towers at SLS into a W Hotel.
Marriott has an agreement with Cosmopolitan, although it has been rumored that will be replaced with Hilton due to Cosmopolitan's recent sale to Blackstone.
I personally don't have a vested interest in either one of these loyalty programs, but from what I'm reading it appears that Starwood customers are worried about having their points devalued by Marriott.