This is actually kind of irritating to watch spread live.
Idiot on RealGm makes up a rumor... some twitter trolls pile on pretending to have similar information... some obscure blog runs with it... a slightly bigger blog runs with that... some garbage media types who don't vet their sources run with it... other media types quote the garbage media types... suddenly it's appearing on CelticsBlog, Yahoo, Sporting News, etc. Meanwhile, the idiot who made up the rumor is cackling his head off. Trust me, I get it... I once made up something that ended up on Good Morning America. But when you're not in on the joke, it's annoying to watch in real-time.
ANyways, a trade for Blake makes some sense. Bill Simmons has been calling this the wildcard trade for months. I'm not surprised this is the fake rumor people are running with. I wouldn't be entirely shocked if something actually happened.