Rovio has taken to their Twitter account today to reveal a teaser image of what they're calling a "big adventure with new birds." Though there have been a couple of new birds added to the mix as well as modified versions of birds in the Angry Birds Star Wars games, the core lineup of Angry Birds has remained the same across all the various iterations of the game. Although the teaser doesn't offer much information, at least it's nice to see Rovio considering introducing some brand new characters.
A follow-up tweet states that more information, including the name of this mysterious adventure, will be revealed tomorrow. Nothing indicates that this new adventure will even be a game, as Rovio has cartoons, a toy line, and all sorts of other branches of their Angry Birds empire that this could apply to. But my gut tells me this will be the next title–not just a spin-off–in the Angry Birds franchise. Angry Birds 2 perhaps? We'll find out more tomorrow.