Cable companies are notoriously tin-eared when it comes to dealing with consumers. But Comcast hopes to show that it can win movie-lovers’ hearts and cash by selling electronic versions of films and TV shows — a business that’s now dominated by Apple’s iTunes and Amazon. The cable giant should begin to sell a few hundred movies and TV shows movies and TV shows to its 20M Xfinity digital customers by year end, I’m told. (The industry term for this is Electronic Sell-Through, or EST.) The main selling point is that Comcast subs will be able to buy the content via their set top boxes, and watch on their TV sets, without the need for an additional device to link them to the Web. Adding cable or satellite companies to the retail mix is “really going to open up amazing opportunities,” Lionsgate CEO Jon Feltheimer told analysts last week, teasing Comcast’s expected announcement.

The consumer proposition has some quirks: Comcast will store EST content on its servers so people can access their movies and TV shows anywhere via the Web. But the content initially won’t be accessible on Hollywood’s UltraViolet streaming platform. Comcast subs who buy EST content, but then cancel their cable subscription, will still be able to access their movies and TV shows — but just via the Web, not on another company’s set top box. Subscribers who buy content via their set top box will see the charges appear on the monthly bill.  Yet those who make the transaction on the Internet will need to charge a credit card, and there won’t be an app to simplify purchases from mobile devices. Pricing is expected to be competitive with iTunes and Amazon, but it’s hard to say just yet how the selection on Comcast will compare. It’s still working on deals with some studios.

These and other complications could make it hard for Comcast to woo some movie buyers from Apple or Amazon. Cable operators aren’t known for creating user-friendly user interfaces — and that could be a problem if the pattern continues. “The most important thing is that consumers can find the titles they want,” says SNL Kagan analyst Wade Holden. Comcast also likely will have to clarify where content will, and won’t work. “If you’re an Apple household and have an Apple TV, it’s easy to put [a movie or show] on an iPad,” Holden adds.

Hollywood wants this to work: Moguls see EST as their best hope to replace the home entertainment revenues lost from the steady drop in DVD sales and the broad shift to low-margin rentals vs high-margin purchases. Some studios, led by Fox, are so eager to promote EST that they offer new films on the platform two weeks before they’re available on DVD. The business is growing quickly. SNL Kagan estimates that consumers will spend $1.97B for EST movies and TV shows in 2018, up from $988.7M this year.

Comcast also has a strong incentive to make the initiative succeed, and not just because it owns Universal Studios. VOD rentals on pay TV are “basically flat after being flat last year,” says Tom Adams, Research Director for U.S. Media at IHS Electronics and Media. “They’re giving so much away for free and there’s a lot of competition for the $5 and $6 rental.”