As part of its Drink Up, Rock Out promotion, Pepsi has launched a new iPhone app in partnership with MTV. It’s called Pepsi Rock Band, and lets people put their own faces on the shoulders of characters from the Rock Band console games.The resulting images can be saved to the iPhone, or shared via email, Facebook, Flickr and Twitter. In truth, mixing photo faces with CGI avatars often looks a bit rubbish (i.e. we’ve been trying all morning and still don’t look like rock gods).However, the app is also flogging songs from the campaign via links to the iTunes Store. Billy Idol, Duran Duran and Motley Crue are among the artists to benefit.