The problem with Visa/Mastercard is that they are unquestionable kings of payments. It is nearly impossible to compete with them, because one would have to build entire acceptance infrastructure (plenty of terminals) and issuing infrastructure (people who would actually use new payment mechanism). There were multiple attempts to do that, but even the best competitors were not able to leave country level.
Yet, Apple seems to be in a very good position to throw down the gauntlet to Visa and Mastercard. Look at the next drawing (2):
The bad (or good, it depends) news is that Apple has no experience in banking, and there is only a couple of banks that could be partnering with the Cupertino company.
Would you trust Apple (iBank) ? Will we see more tech companies going to finances?
Being a somewhat luxurious brand means that Apple can win only a small fragment of the payment market, and this is not enough to strike a deal with many different acquirers and cut out Visa and MasterCard.
Said that - Apple Pay is a nice feature for Apple users, but being alone is just a nice feature.
But if Apple released Apple Pay as an open solution... things could change significantly. We would see many wearables with Apple Pay, and that would open the possibility to negotiate with acquirers...