Bitcoin is showing no signs of slowing, soaring towards a record US$10,000 just hours after breaking $9,000.

Late last week, America's largest bitcoin exchange Coinbase added about 100,000 accounts over the Thanksgiving holiday, coming to a total of 13.1 million.  That's more than double the number of accounts from just a year ago.

But even as Bitcoin achieves more traction in mainstream circles, there are increasing warnings of a "Bitcoin bubble".  DBS bank is Southeast Asia's largest lender, but group chief information officer David Gledhill says, "We see bitcoin as a bit of a Ponzi scheme."  For consumers, Bitcoin transactions are "incredibly expensive" and "all the fees are hidden through the crypto-mechanisms". 

Last month, JPMorgan Chase CEO Jamie Dimon was a little more blunt, warning that those "stupid" enough to buy bitcoin will ultimately "pay the price for it". Attorney and financial comentator Jim Rickards usually disagrees with Mr. Dimon, but says: "I call it a Ponzi with no one in charge," and adds, "Bitcoin has not been combat tested in a business cycle. We have not had a recession or a financial crisis since 2009."