Apparently the combo wiped all data from Starwood hotels. At least the LM I'm currently staying at told me ALL prior stay and preferences disappeared - but here they MANUALLY transferred at least the preferences (and stay info as well since I was ug to the suite I have been in many times) and a unique request I have was already in the room.
I can't imagine how much work it was to manually update all the info - but I'm guessing not all properties are going to do this. I would have thought the higher end properties would have done this but apparently not.