I'm a long time Hyatt Diamond, and close enough to Lifetime Diamond that it looks achievable. I suspect this combination will actually lead to an increased number of Hyatt stays/nights for me. I'm a low level elite with both Marriott and SPG, but I did chase promos with both chains, resulting in stays that could have easily been with Hyatt. Once the programs combine, I assume there will be fewer promos and thus fewer stays.