As Twitter prepares for its IPO, we can all expect to hear a lot more about how important the service is to consumers who watch TV. Facebook has also been busy proving that its service is vital to TV viewers who twoscreenshare their feelings about shows and sporting events they’re watching. In both cases, the services are courting TV marketers.

Each one of these services would like to reign supreme in the social universe. A recent New York Times report by Vindu Goel and Brian Stelter cited statistics that these services promoted regarding the final episode of the  popular Breaking Bad series which drew over 10 million TV viewers. Twitter had up to 600,000 users generate 1.2 million messages, tweets and retweets, during a 10-hour period. Facebook claims that up to 3 million users had something to say about the series, though this includes users who ‘liked’ what another user had to say.

These are all people that marketers would love to reach. Marketers are still spending the bulk of their ad dollars on TV but social network operators see an opportunity. eMarketer data indicates that up to 50% of U.S. consumers are on social networks while they watch TV and 1/6 actively comment.

Analysts say that sporting events, more than any other type of programming, generate ‘the highest engagement’ of two-screen activity. Nielsen data indicates that these live events, while just a fraction of all TV programming, account for nearly 50% of tweets. This activity is driving marketers who want to reach the sports audience to buy advertising on social networks. The reach of Twitter far exceeds the number of tweeters – these messages also reach the followers of each consumer who posts.

To stay competitive, Facebook will be adding a video ad format to its site soon. The company will attempt to sell marketers on the value of this platform, especially with respect to consumers who are carrying around tablets and smartphones and will be viewing messages while they shop.

It’s too soon to know how much of the TV ad budget will be captured by social networks but it’s a trend worth watching.