If a network like TLC or Discovery's picking it up, they're going to want American cars on it to draw the largest possible audience. Hopefully, they'll do some stuff like take the American Ford Focus and compare it to the European Ford Mondeo and show people just how bad the swill that's sold to us is.
As for the import/domestic car thing, about the only way you can classify them anymore is by where the manufacturer is located. Yes, BMW does have plants in the US and does by parts -- but their overall domestic presence is still pretty small compared to GM and Ford. Toyota's running ads saying how great they are for America -- yet they only employ 1/6th of the people GM does.