Well, I briefly scanned through some of the comments here, one thing I didn't see mentioned was the fact Coin is not rechargeable, once it's dead, you are required to buy a new Coin.
Apparently according to plastic, it is rechargeable, therefore once you buy it, you never have to buy another. Another interesting point was it's wireless rechargeable from the video, which is interesting.
This is Coin with a larger e-ink display, NFC and "Chip and PIN"