E4's Misfits was a game-changer! The producers embraced transmedia storytelling from the get-go! Read the Six to Start case study here.
Fans of the critically acclaimed US television drama Mad Men had previously leveraged the power of social media and created fictional Twitter accounts for the Drapers and creative folk at Sterling Cooper. But, the network baulked at the idea and tried to close the profiles and blogs down, which was, ultimately, counterintuitive and self-defeating. The fans won a reprieve once the studio understood the positive benefits of raising awareness via the social media space. When there's goodwill, it's a win-win.
It's no surprise to see hit series Glee (Popular meets High School Musical) utilising social media:
Official Glee on Twitter
Glee
Official Glee Cast on Twitter
Cory Monteith
Lea Michelle
Amber Riley
Harry Shum, Jr.
Chris Colfer
Naya Rivera
Jenna Ushkowitz
Dianna Agron
Dijon Talton
Kevin McHale
Mark Salling
Matthew Morrison
Official Glee Characters on Twitter
Quinn Fabray
Rachel Berry
Sue Sylvester
Kurt Hummel
Official Glee Cast on Tumblr
Harry Shum Jr.
Dianna Agron
Matthew Morrison
Sue Sylvester is a compulsory follow as suggested by @petehotchkiss. This list is by no means definitive. If I've missed any, please put them in comments or @johnhood, and I'll update. Thanks in advance.
E4, an independent commercial network in the UK, even went as far as using #glee4 during television trails for Glee S1. That's a masterful mashup of old and new media marketing.
Purchase Glee merchandise from Amazon.co.uk, Play.com and iTunes.