I think Moyes has his own small "empire" at Goodison Park. Good players, good squad. I think he's happy there, respected by the fans and I would be amazed if he decided to move away.
Pessimistically thinking he probably would be the only manager who's , in worst case scenario, failure as a Villa manager would be (bitterly) accepted. I believe everyone else's short term failure would soon bring the "whateverhisnameis OUT" banners back.
So, if GH decides not to continue, the new manager must get things right from day one. Whatever happens it would be nice to see the fans backing the manager, current or new, welcome him and give him time.
I hope Houllier will be back.