My dealer in Princeton, NJ said the orig oil change should be at 7500mi(a lot but makes sense).
Then he told me that the regular oil changes should be at 3750 or so. The reasoning is that the engine stop feature at lights now. This results in severe (stop and go style) duty on the oil and as a result it needs the changes often. Also makes sense.
I do plan to eventually go to synthetic (Amsoil) with guidance of oil analysis. More later.