The company has earmarked $270 million as 50% of the production budget for three films. They will be looking for international partners to pick up the rest of the budget, which given who they've worked with in the past (they've co-produced everything from Iron Man 3 to Looper) probably won't be hard.
The first two movies will be The Way of Kings and Mistborn: The Final Empire. Exactly how they're going to boil those books (especially Way of Kings) down into a single movie remains to be seen. They've already appointed writer-producers to Way of Kings and are prioritising the project on a fast-track to the screen.