Being a life long resident of Old Bridge (minus a few years up in Harrison, with my now, wife), I've always considered Old Bridge as Central Jersey. Anything North of "the bridge" (which covers Driscol, Edison and whatever they call the new Route 35 bridge) is North Jersey. The "shore" was always Pt Pleasant/Seaside and South Jersey was anything South of that (AC and Wildwood were the only 2 places we ever cared about as kids).
My wife, on the other hand, a life long North Jersey resident until I moved her down to the sunny suburbs of Old Bridge considers anything south of the bridge* (see above) to be South Jersey or The Shore. I have explained that Old Bridge/Sayreville is merely "The Gateway to the Jersey Shore", but she doesn't get it... Bennies...