We've seen plenty of versions of Angry Birds over the years, and it looks like another will be coming. Rovio has yet to offer much in terms of specifics, however they have said Angry Birds Transformers is happening. The confirmation was posted on the official @AngryBirds Twitter account where Rovio mentioned how "it's happening" and offered a link to a coming soon style teaser page.
The Angry Birds Transformers site has just the basics for now. There is a mention about how this release is "coming soon" and will bring "birds disguised as robots in disguise." Nicely, we were also given a first look at the birds, or maybe more accurate, the "birds disguised as robots in disguise."