From Variety:

After "Transformers: Dark of the Moon" hauled in more than $1 billion at the global box office, Hasbro is eager to keep its toy-trafficking franchise rolling on the big screen -- to the degree that plans are being considered to shoot the fourth and fifth installments back-to-back.Hasbro chief Brian Goldner said during a Monday third-quarter earnings call that the toymaker is in "active discussions" with Paramount, Michael Bay and Steven Spielberg on how to move forward. Sources close to the planning process tell Variety it could actually be two films headed into production.

With tentpole costs pushed by contract negotiations, escalating f/x coin and the need to plan toy designs and merchandise tie-ins more than a year in advance, Paramount, which licenses "Transformers" film rights from Hasbro, is considering lensing its fourth and fifth films without pause. Nothing is set in stone, but screenwriter Ehren Kruger is said to have an idea for the next installments that the studio is high on, and has only begun engaging with writers.

One element that won't return: Shia LaBeouf, who's said he's moving on, giving Paramount the chance to pair a new face with the shape-shifting robots. Though one name -- Jason Statham -- has been bandied around by sources close to the production, no offer has been made.

While Bay will serve as an executive producer alongside Spielberg, sources close to the development said Bay is still interested in directing. Bay has wanted to spend some time on his competitive body-building passion project "Pain and Gain," which he could conceivably squeeze in before "Transformers" got going in late 2012 or early 2013.

Helmer is also a creative consultant to "Transformers: The Ride -- 3D," a big-budget theme park attraction under construction on the lower lot of Universal Studios Hollywood that opens next spring.

Although Par has never shot sequels back-to-back, the way the second and third "Matrix" and "Pirates of the Caribbean" (and soon Universal's "Fast Six" and "Seven") were produced, the strategy pays off in advance, with cast and crew under contract for both pics.

It would also give Hasbro more time to design new action figures and playsets to fill store shelves. The series has been a massive moneymaker for Hasbro, with the first film in 2007 generating $482 million in "Transformers" toys alone, and more than $600 million around the second, providing a case study on how toymakers can capitalize on film and TV shows based on their popular playthings.
"Dark of the Moon" earned $1.1 billion, putting it in the fourth spot on the all-time box office list. …

http://www.variety.com/article/VR1118044618