That is really cool! I don't drink coffee, so it is useless for me, but could lead to self heating soups and other products in the future I'm sure. The possibilities are unlimited really! I would like to see more on the can technology, how its done etc...but that is really neat. I'd buy soups or something like that though.
You sure thay actually have it now? I remember a few years ago when Popular Mechanics (or pop science, or one of those mags) got taken in by a hoax about "self cooling cans". I don't see any reason why it couldn't be done (not that I'm a chemist etc), but I can remember at least two times that such a product announcement turned out to be a hoax. At least the "self-heating" announcement looks like the real thing.