MTV has yet to decide whether to order a second season of Jersey Shore but the latest ratings should speed up the process. Last night’s finale of the now-notorious reality show, following a group of people renting a beach house at the Jersey Shore, averaged a whopping 4.8 million viewers and a 4.8 rating in the age 12-34 demographic. That’s a 30% increase over the previous series high in that key demo. MTV reports that Shore posted incredible growth over its abbreviated season and the finale audience more than tripled that of the series debut. Many viewers also stuck around for Jersey Shore: The Reunion immediately after the finale; it delivered a 4.0 rating among persons 12-34 and attracted more than 4 million viewers.