Magic Lantern is working on a true RAW and 14 bit video recording along with 4:2:2 to the card, something we'll never see from Canon.
And they've already said it will never be something that will work for video people...best they've gotten so far is 720 at 24fps for 2s...the reality is you'll never get long recording times because the camera has a buffer to deal with. 1080p wont happen.
Really, it's an upgrade for time lapsers and may have some cool other uses.
If this is the case, the soft output of the 5DmkIII compared to other cameras, as documented on many of his tests, may in fact be impossible to fix with a firmware update, at least one from canon.
That said, what they did find interesting was that the resolution of the DNGs they got from their RAW mode were way higher resolution than just the traditional h.264 video stream from Canon. Not sure if that means that Canon intentionally is crippling it, or if the h.264 encoding loses a lot of resolution, but, that could be useful for some purposes.
Of course, if you want Raw video at 2k, you'd just spend the same amount on a BMCC instead and get a much nicer workflow.