While at first it seemed strange that Microsoft would only now be hiring for the project, Microsoft followed up with MTV to clear things up. The company told MTV, "Microsoft Game Studios has been hard at work collaborating with Peter Jackson and Bungie on the development of [a Peter Jackson-helmed Halo project]. At this time, it's necessary to grow the internal team to keep pace with development. Bungie will continue to remain involved in multiple aspects of the Halo Universe with MGS." So, it turns out that the project's development team is merely expanding -- as opposed to just now being formed -- which would indicate the project has become more expansive as well.
Let's hope we can hear some news about the actual game sometime soon. Seriously, we're starving for info.