It's not so much an oil shortage but more of an issue with refinery capability.

Iran imports all of its refined fuel even though it exports oil. 

The demand for oil continues to build with 3rd world nations now becoming growing economies on a grand scale.  The refining capabilities have grown very little, if at all, by comparison to the demand.

Alternative fuel technology should be the next big boom....but then Washington has been saying that for 30 years.