Nuclear plants don't make smoke, they make steam :P
These are just a fad.. a somewhat interesting fish but one that's only claim to fame is the novelty of being a neon'ish color. The hobbist don't seem to be buying it, so it'll die out on its own most likely. Or at the very least, new hobbist will buy them, come to forums like this for information, find out most people disagree with glofish, and go buy real fish