Not mandatory, just (barely) incentivized starting in 2015. You'll see non-EMV cards and terminals around for probably another decade.

This is highly doubtful. The fact that merchants take on all fraud risk from a fake card present transaction is very high incentive. I have friends in Canada that own retail stores and they said that fraud has dropped to almost zero because of EMV. There are ways to scam it, by pretending that the chip doesn't work and have the cashier swipe it, but if the cashier swipes it instead of using the pin, they get in trouble because the merchant loses money.

So I bet you'll see very quick adoption, within a couple of years max.

Big box stores are already moving towards it, with Target (surprise! surprise!) leading the way. Mom-and-Pop shops will probably not be happy about replacement costs, but they're apparently a diminishing market force anyways.

Experience from other places that switched to EMV shows that this incentive is large enough to have a rather quick adoption. Yes, there are some niches where non-EMV terminals stick around - those that are low-volume and feel immune to fraud; but all common stores seem to switch quickly as otherwise all fraudsters focus on those who haven't switched yet, and low-margin business can't afford losing that money.