[mrits]

"When an asset class becomes so popular that people who have no idea how it works are putting money into it and loudly campaigning for others to do the same that is a sign that you are in a bubble."

It absolutely isn't a sign a of a bubble. There aren't many people that understand what they are investing in be it currency or Google. The success of the investment has nothing to do with the cabbies understanding. Taking his advice does.