He'll still be consulting producer, won't he? I've heard several writers quit because of this too, though, so that's not good.
On the other hand, some shows actually get better once the creator takes more of a back seat (Angel comes to mind).
And even if the last season tanks, the last three episodes of season 3 will be a perfect send-off of 'good' Community. Digital Estate Planning was incredibly awesome. I need to watch it again while freeze-framing, so many references and easter eggs in there.