Ken from Vegas wrote:
We always use our cards and have only had two times when we couldn't. One was in the Amsterdam train station where the ticket seller wouldn't take a card without a chip (I think she was just ignorant of how to run a card otherwise). The other was in Switzerland, where we couldn't use our card in a ticket vending machine. Most all restaurant and stores in France have machines that take either style card.
By the way, the new American cards with a chip are "chip and signature" rather than "chip and PIN." I wonder if you'll be able to get a PIN for travel or if you'll have trouble with those in Europe where they expect that a card with a chip will have a PIN, too.