Around these parts - BBQ is whatever animal you can fit on the smoker. Sausage is for all the extra, leftover, bits. Brisket and ribs are probably the main item, followed closely by pork. Down the list is chicken and sausage.
I think it's kind of neat how Q varies among different parts of the country.
Mind you, we smoke just about anything as well. But when we say "barbecue" with out qualification, it is PORK.