Halo Composer Fired "Without Cause"

Composer of the main theme to Halo and much more, Marty O'Donnell was part of Bungie before they were bought by Microsoft in 2000. He remained a part of the developer up to yesterday, when he sent out this tweet:

I'm saddened to say that Bungie's board of directors terminated me without cause on April 11, 2014.

— Marty O'Donnell (@MartyTheElder) April 16, 2014

Nothing has been said officially by Bungie, and what this means for the mysterious Destiny, which O'Donnell had recently been working on.