Originally Posted by msp3

Ritz-Carlton and Marriott Rewards are basically the same, just what sort of marketing materials you get. Your Marriott side account is either Marriott or Ritz-Carlton, so link appropriately from the SPG side.

If you want to do all your stays at Ritz-Carlton, call up Marriott and get it changed from Ritz-Carlton to Marriott. Everything stays the same except you get Ritz-Carlton's emails and promos from now on. I just did earlier today.