AT&T isn't about to sit on its thumbs while Dish's Sling TV scoops up people eager to ditch conventional TV. It's introducing a trio of DirecTV streaming services in the fourth quarter of this year that won't require a satellite dish or existing AT&T services -- your phone, PC or media hub will be fine. The core service is DirecTV Now, which will offer "much" of DirecTV's regular live and on-demand content. If you're only interested in handheld video, DirecTV Mobile will offer a mix of "premium" videos and digital content on phones. And if you just want a peek, DirecTV Preview will give you a free, ad-supported slice of content from the networks and Otter Media, AT&T's online team-up with the Chernin Group.