Mark Wahlberg will be returning but so far no other cast has been officially announced.
The film will be written by Akiva Goldsman. Goldsman won an Oscar for A Beautiful Mind, but he also wrote Batman and Robin so it could go either way as far as quality goes.
The other big news is that Paramount will be making an animated Transformers. This will be an prequel of sorts and take place on Cybertron. The animated movie will be written by Andrew Barrer and Gabriel Ferrari who did some rewrites on Ant-Man.
There is no word yet on any of the plots of the movies. But the ideas came out of a writers room that consisted of Zak Penn, Robert Kirkman, Christina Hodson, Lindsey Beer, Matt Holloway, Jeff Pinkner, Geneva Robertson-Dworet, Steven DeKnight, and Barrer and Ferrari. Goldsman oversaw the writers room which saw 5 story lines emerge.