...(The director, by the way, says that the fourth film will include some redesign of the robots and an entirely new cast. He also said it will be his last and set the franchise up “for the next guy.”)...
..says THIS piece over at Hero Complex.
Nothing Earth shattering, but ...as far as I'm aware, at least...this is our first pointed (and semi-official) confirmation that the next film will 1) be a wholly new cast (a rumor/likelihood previously alluded to by Josh Duhamel) and that the Transformers themselves will be re-worked a bit for the forthcoming picture.
The new movie is due in theaters Summer 2014. The previous instalment, TRANSFORMERS: DARK OF THE MOON made 1,000, kazillion-jillion-buhzillion dollars (that's over $1 billion) globally.