Warren Buffet is an intelligent person. However, he is also a dinosaur from a dying age. If you read the article (not to insinuate that you haven't), he doesn't say it's going to fail, crash or whatever.
He says the BTC is an incredibly volatile "investment" and not for the faint of heart, which I'm sure we can all agree with this statement. That said, we are all gambling for the future, and he is living in a paradigm that is quickly disappearing. I mean, look at what Jamie Dimon has said, back-peddling about his previous claim that BTC was a scam, now he says it's not a scam but will be controlled by the Feds. We still have a long way to go, but I'm in it for the long haul.
Good luck and HOLD FAST.
P.S. Followed you and resteemed this post.
Thank you radagast and good luck with your investment :) At which point of the mostly increasing curve of the bitcoin, you've done your investment? I'll try it with ne new NAGA Coins.