Via GameDaily.biz, Hasbro Investor reports that a new Transformers game is currently under development, most likely for consoles and/or Steam! Developed by Certain Affinity - a company with few full games under their belt but solid bonafides for shooters that dates back as far as Halo 2 - the game is expected to once again be a third-person series as the High Moon Studios games were. (With High Moon themselves currently indisposed as permanent backup for Bungie on Destiny, sadly we don't expect to see them return to the franchise.)
Little is known about the game other than its tentative title of "Transformers Online," its developer, and its genre - but there's also a disclosure of acquisition from a company with a 20% stake in Certain Affinity that mentions that their specific license to Transformers covers the G1 period of 1984-95, and the modern "Generations" setting. If we were betting, we'd expect this game to tie into the War For Cybertron trilogy, and if so we hope they will title the game very carefully to avoid confusion.
Activision have recently ceased their association with Bungie, meaning the studios High Moon and Vicarious Visions are now free to work on other projects.