The amount of available data about viewer behavior has expanded exponentially in recent years. But programmers complain that the access to this all-important information--which will give them keys to understanding huge changes in their now multiplatform audiences--is being tightly controlled by MVPDs, as well as platforms like Facebook, Netflix and Twitter. Having covered her publication's "TV Summit" event in Century City, Calif., Variety editor Cynthia Littleton has collected some interesting perspectives here.