From all the hullabaloo in certain corners of the internet, you might think there were tens of millions of people just waiting to give HBO or AMC fistfuls of money to watch their shows in real time without having a cable subscription. But more than a year after the release of Sling TV — Dish Network’s internet TV service — the revolution is slow going, and not just for Sling. In fact, we now have a reasonably comprehensive view of this “over-the-top” market: HBO Now, which launched in April 2015, has 800,000 subscribers, per HBO President Richard Plepler. Sling TV, which is essentially a small cablelike bundle and includes live ESPN and AMC, has somewhere between 500,000 and 600,000, depending on which analyst you ask. CBS All Access, which launched in 2014, is estimated to have 500,000.
Source: The Sling TV Dilemma: Why Aren’t More Cord-Cutters Flocking To Streaming Services?