For small traders, oil rivals Apple in popularity

Time and again, Apple is the most popular stock among retail traders on a daily basis. This week, the tech juggernaut got a little competition ... from oil.

It's not often that you see commodities—volatile vehicles that trade more on macroeconomic and chart factors—become as popular as individual stocks, but that's exactly what has happened, according to data from 6 million accounts at TD Ameritrade.