NEWSNIGHT: Bitcoin -- the future, or a bubble waiting to burst?

Bitcoin, the subversive virtual currency, is now recognised by the Fed. So what now? Digital currencies bypass government and with it, central banks, regulation and oversight. It's the thing that makes them so attractive. But does this lack of control, and their volatility, mean currencies like Bitcoin can never replace dollars, pounds and yen? Finance broadcaster Max Keiser and economist Jeremy Cook, of World First, debate.