For those who would be opening a new card, 12 months on a Mac really isn't that great. You can get 18 with a Barclaycard or 15 AND a way better cash back/points bonus on many other cards' intro offers.
Long-term, "Anytime" 0% financing (vs. intro offers) is definitely a perk that will have its market, but I still think there are better card options out there for many who want to carry a credit card when you consider rewards structure and other benefits.
The initial rumors about this coming had me considering Apple Card (I'm in the market for a new CC and Mac, only makes sense to time them for reasons noted above), but I think I'm looking elsewhere now.