Twitter's new feature is called See It, and by November users will start having the ability to "expand" tweets about certain NBC shows, like "The Voice" and "Sunday Night Football".
Expand a tweet, and users will get more information about a show and, if they are a Comcast subscriber, be able to watch or record the show directly through Twitter (though they will have to login to their Comcast Xfinity TV account first).
This deal gives Twitter the opportunity to prove to TV networks that it really can turn its users into active television watchers-like it's been promising all along.
The news represents a major leap forward for Twitter when it comes to the battle for social TV domination. Twitter and Facebook have been volleying back and forth, most recently with Facebook's new data sharing initiative and Twitter's launch of its partnership with Nielsen.
Comcast has no plans for partnering with Facebook, as of now.