A couple of points
Retailers are not required to upgrade to EMV. I'm sure a lot of retailers will meet EMV specs, but the Liability shift is a a paper tiger.
Apple Pay is not the same as NFC. Even Apple stated that retailer EPOS systems must be updated to support Apple Pay. This has somewhat to do with Apples implementation of NFC.
I may be mistaken, but I believe MCX Membership rules require exclusivities. And MCX has a large number of member companies, not just Wal-Mart and Best Buy. (
www.mcx.com)
I'm not sure if MCX will gain traction, but I believe it has a better chance than ApplePay.