It was a Gold Rush year for online marketplace lending.

The sector’s undisputed leader, Lending Club, more than doubled its quarterly loan volume on its way to a lucrative initial public offering. Hungry for yield, a deluge of new capital from hedge funds and other institutional investors rushed in. Bankers sat up and took notice. New asset classes — including small-business loans, real estate loans, and even loans for the purchase of solar panels — were pioneered. An ecosystem of ancillary firms matured. By December 2014, roughly 100 different online platforms were operating in the U.S., according to one estimate.

As a result of the industry’s rapid growth and evolution, American Banker has named marketplace lending its Innovation of the Year. Now, The Big Question is not so much if but when will Federal Regulators step in and screw it all up while pretending to do so for our own good.