My F1 2010 drivers championship outcomes

Current standings
Alonso 246
Webber 238
Vettel 231

Race position/Points/Championship position

Webber 1	263	Webber
Vettel 2	249	Alonso
Alonso 3	261	Vettel

Vettel 1	256	Alonso 2
Webber 3	256	Vettel (5 wins)
Alonso	261	Webber (4 wins)

Vettel 1	256	Alonso
Webber 2	256	Vettel (5 wins)
Alonso 4	258	Webber (4 wins)

Vettel 1	256	Vettel (5 wins including most recent win)
Webber 2	256	Alonso (5 wins)
Alonso 5	256	Webber (4 wins)

Vettel 1	256	Vettel (5 wins)
Webber 2	256	Webber (4 wins)
Alonso 6	254	Alonso

For Webber to win, he has to win the race and Alonso has to finish 3rd at best.
For Vettel to win, he has to beat Webber and Alonso has to finish 3rd at best (doesn't matter who comes second).
For Alonso to win, he has to beat the Red Bulls in any order and any position as long as he's ahead (as well as some other unlikely outcomes).
For Hamilton to win, the above 3 would all need to crash out or retire which is unlikely.

I would say from various driver and community comments that if Red Bull are 1/2 - Vettel/Webber, it would be no surprise if Vettel was told to let Webber through so he could take the drivers championship, otherwise Vettel would not give up his position.