I read this from survivorsucks.com in the news section:

Mark Burnett has shed some light on what the final episode's immunity challenges will be, and the selection of the final survivor:
The first immunity challenge...
Foreign Comrades:
The four remaining survivors must answer questions about the 12
castaways who have been booted from the island. The only way to win this one is to have cared enough to listened to the others while they were around. (Is it possible for no one to win this one?)
The second immunity challenge...
Fire Walk:
This challenge is a mind-over-matter walking on hot coals
challenge. The winner of this challenge picks who will accompany
them to the Final Two.

The big one...
Closing Arguments:
The final two survivors will plead their cases before the Jury of Seven - the last seven castaways kicked off the island. The jury will then select the million dollar winner.

~~Emie~~