Late to the party...

I grew up in Boston so my English is a mish-mash of AmE and BrE complete with misspellt words (to an American) and odd constructions ("so aren't you").

Having said that, I want to urge everyone who generalizes about groups to stop doing this. There is no standard "American" English anymore than there is a standard "British" English.

People tend to talk and write based entirely on where they were raised. Communication is the most important thing to remember. Languages are fluent and change.