Daniel Bader over at Mobile Syrup has a nice little FAQ about Apple Pay in Canada.
The long and the short of it is you need an Amex card, and an iPhone 6/6 Plus or newer, or an iPad Air 2/mini 3 or newer. The big retailers that accept Apple Pay so far include McDonald's, Tim Horton's, Petro-Canada, and Esso.
First, Apple Pay is built into the operating system, so there’s no need to open a separate app as you do with a supported banking app, or a third-party solution like UGO Wallet or SureTap Wallet. Apple Pay also natively supports the iPhone’s Touch ID fingerprint API, obviating the need to enter a separate PIN code.
Apple is also the first mobile payments provider to use a confluence of security protocols, such as unique device and transaction identification, as well as tokenization, which randomizes the associated credit card’s primary account number (PAN) so that in the event of a data breach or theft, the actual credentials are scrambled.
Second, when compared to a plastic credit card’s in-store $100 tap-to-pay limit, Canadians using American Express are only subject to the limits of the merchant’s card machine, or their own card’s credit limit, which is usually much higher.
I got mine set up in about 2 minutes last night. It was easy. But, I haven't had a chance to try it out yet.