On CodeIgniter.com today there's a new blog post hoping to clear up any confusion about the Community Branch of the framework and the NDA that would be required for those developers on the project.
The confusion lies in the purpose of the NDA, and the scope of what it covers. The branch's development will not be under NDA, nor will discussions between the deputies and the community, how they receive code submissions, what they reveal to others about their own plans, and so on.
The NDA does, however, cover any discussions that might be had with the EllisLab group about the structure and guidelines concerning the development of the branch. It's not designed to keep the community out of the development process but rather to keep things about ElliLab's other products out of the larger flow of ideas.