One more question, why do you think it was adopted so much faster than Apple Pay?
Because it works on existing magnetic stripe terminals, which is everywhere you swipe your card today. The merchants don't have to do anything to prepare for Samsung Pay.
The only problem with Samsung Pay is lack of bank support... But if you have Citi, Bank of America, U.S Bank, Key, Chase, American Express, and some others, you should be all set. I know Discover and Wells Fargo are planning on supporting it soon, but I'm sure it's not as simple as just flipping a switch.
Hopefully when Discover begins to support it, they'll have a similar promotion like they did with Apple Pay, the additional 10% back, plus your normal percentage back of what you get, and then doubling it after your first year.