That, and Microsoft realizing that they need more studios to feed Xbox and PC with exclusive content. Also, developing in-house would certainly mean more control over where the IP is heading.
Just waiting for Microsoft to call the Studio Ensemble Studios...
I had a feeling they would need to do this at some point. They need to feed Xbox gamers with something exclusive, but that would also dampen their newly (for the 4th friggin time) branched relationship with PC gamers, so they'd need to make something exclusive for them.
MS would either have to make everything for both platforms or make something special for each of them, or simply risk losing one side again.
Happy to see them finally making another RTS studio, after years and years, but I do not want them breaking this studio down, after a few years, the way EA did with Victory Bioware.