Meh, I'm not really in a tizzy either way about this. But then, all my favs have already been whisked away so what do I know. If it's confirmed by TPTB and co. that he's leaving (and hopefully not in a body bag ) then I say more power to him.
It's possible that he wanted to free up his schedule to do more films. He seems to get quite a few flicks as of late.