Most is probably being used for savings as the potential for it to increase in value over years is ridiculously high. If bitcoin succeeds in taking over fractions of global markets, which is is poised to certainly do because of its efficiencies, then the market cap will be hundreds of billions, and valued above several thousand dollars each.

But, bitcoins are being used in commerce too. New merchants added every day. I know of at least 6 brick and mortar businesses in Las Vegas alone that have sprung up recently.