Check out this Infographic from Kristin Piombino. It talks about how many companies use social media the wrong way, but a lot use it to their advantage. ABC for example, uses PanAm on twitter. Viewers who use twitter can use the hashtag for PanAm, and also listen to the Pandora station that ABC has created with music from the era. If there is a hashtag on a show, I always use it to tell my opinion on the show. I watch Suburgatory on ABC, and they often use a hashtag in order to have their viewers talk about it.
This also reminds me of the Groundswell, where these companies are letting their viewers create a community around their product. When you watch a show, often times you call your friend or family member to talk about it. Instead of doing that on a 1-1 basis, companies, like ABC, are encouraging their customers to do it within a community. Using Twitter to have your viewers market your product for you seems pretty genius to me. They get all the publicity they need from social media with one hashtag.