I would imagine that 'something' will happen in the future, the way technology is advancing means it's pretty well bound to, and there's an awful lot of money been spent on new energy sources (much by the oil companies, who would
VERY much like something to replace oil revenues when oil runs out).
And who knows, it could be
YOU!! that discovers it
I do think though that over the future oil is going to become less of a fuel (replaced by something else), and more of a source of plastics.