The view order info link doesn't show the tracking number for Canada Post so I have no idea if someone accepted/stole my sim card or there was a problem with the delivery.
I do not have exact details of when and why they have made changes to processing some orders but not others, but Public Mobile no longer ships all sim cards by and Canada Post Xpresspost. Some sim cards are still being shipped by Canada Post, but as a letter. If that's done, there is no way to track the shipment. As to the roughly 2 week time that you've been waiting, that's actually not too bad, considering. I know that's not what you want to hear, but I've found that standard lettermail is sometimes taking 3 to 4 weeks to arrive across Canada.