When one of my friends figured out how to barbeque bratwurst he was one happy camper. Literally. We were camping at the time, and he was ecstatic about how much better they were barbequed instead of just grilled. No barbeque sauce on them either. Barbeque is a method of cooking that has nothing to do with sauces. I'm from Michigan and can't get much less southern, but I know that.
I talked to a fellow at "The Big Pig Jig" (a big BBQ cookoff in middle Ga.) and asked him what the different terms meant.
He said:
Grilling= high heat,
no lid on the grill, super fast cooking.
Barbequeing= medium heat,
with the lid down, medium to fast cooking.
Smoking= low heat, lid down ("if you lookin', you ain't cookin') long term, all day, super slow cooking (called "low 'n slow").
I personally like method three, slow smokin'....leaves a lot of beer time while sitting at the grill.