Indulging TV Binge Viewers: Comcast Joins the Feast

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The term "binge viewing" first entered the mainstream when Netflix started talking about the way people streamed its content—entire seasons at a time. Now Comcast is embracing the trend, bringing TV networks on board to host a "watchathon."

The company has wrangled more than 30 TV networks into offering more than 3,500 shows for free and on-demand for its Xfinity Watchathon the week of March 25. Comcast is opening the doors to premium content, giving XFinity subscribers access to channels not included in their subscriptions, including top shows from HBO, Showtime, and Starz, as well as AMC and others.

Not so coincidentally, this binge week comes just before the new season of "Mad Men" launches on AMC in April and HBO's "Game of Thrones" starts up again on March 31.

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Comcast is helping viewers get caught up, and then they might start paying for those extra channels when the new shows return. And perhaps most important, it's a reminder of just how much value that monthly cable bill delivers.

The cable giant is hoping to keep current subscribers from cutting the cord and to lure in new subscribers, perhaps the "cord nevers" who haven't yet gotten the value of cable when they can stream so much content on Netflix, Amazon, and Hulu.

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If this works, Comcast may also get networks on board with the idea of offering their content on-demand. The idea is that if people can catch up on a show, they're more likely to watch new episodes in real time. And that's the holy grail for advertisers.

—By CNBC's Julia Boorstin; Follow her on Twitter: @JBoorstin

Disclosure: Comcast is the majority owner of NBC Universal, the parent company of CNBC and CNBC.com.