In the spring of 1980 ”Dallas” ended its season with the biggest network television cliffhanger ever. Viewers waited all summer to discover who shot conniving oilman J.R. Ewing; when CBS finally provided the answer that fall a record 76% of American TVs in use were tuned into the show. In that pre-Internet pre-podcast pre-TiVo world networks had only each other to compete with. Today under pressure from on-demand media networks are using new tricks to retain viewers. Their strategy this time around? Turn shows into communities and viewers into cult-like fanatics. ABC’s ”Lost” is probably the most visible example of this recent phenomenon but it’s not the only one. What strategies are networks and advertisers using to gain the attention of that ever-important consumer?