Either the new company takes over maintaining Android, or it fumbles the bag and the development becomes less centralized for a while - until some leader emerges and takes over.
Either way, the new control center of Android wouldn't be Google. A decade ago, I would have seen that as a very bad thing. Now, I'm almost certain that this would be a change for the better. Google is not what it once was.
Well, there is barely any new Android feature worth talking about for the past three years (no, new skins definitely don't count). I seriously doubt there is going to be any change in the market share if Android were controlled by a different company. We would have already seen that by now.
Either way, the new control center of Android wouldn't be Google. A decade ago, I would have seen that as a very bad thing. Now, I'm almost certain that this would be a change for the better. Google is not what it once was.