Most US refineries are optimized to process heavy and sour imported crudes.
US refining capacity is running near full capacity and it is almost impossible to build more capacity given our environmental laws.
Therefore the most efficient use of our crude may be to sell it on the export market.
More US oil on the market could lower the global price of oil, making the imports cheaper as well, potentially relieving some of the pressure at the pump.
Most of our new increases, yes, but not most of our production, not yet.
Increases in U.S. crude oil production come from light, sweet crude from tight formations
http://www.eia.gov/todayinenergy/detail.cfm?id=16591
JUNE 6, 2014
Complete report:
http://www.eia.gov/analysis/petroleum/crudetypes/pdf/crudetypes.pdf