How long more do you think Alex Furguson will stay on with Man United?

Its quite obvious at this point in time that he'll be staying for now. But for how long? Only he can answer that question. The old trafford faithful would want him to stay on for years to come but with age catching up, I guess he may retire by 2011. Its just an assumption based on my thoughts that United will have overtaken Liverpool's haul of 18 titles by then and also maybe have won another champions league title. He's definitely achieved it all with United and its only his personal ambitions and passion for the game that have kept him going. Atleast I don't see him retiring next season. The rest is all his choice. We can just hope he stays and so does Tevez.