Survivor: All Stars 2
It's set in Palau.
Likely contestants (Thanks to Nutjob of TWoP, and the source, TVSquad):
From Survivor 9: Vanuatu: Julie Berry (5th place finish, Jeff Probst's love interest? Hmmm), Eliza Orlins - 4th place, Ami Cusack - 6th place finish.
From Survivor 10: Palau: Katie Gallagher - finished 2nd, Ian the Dolphin Trainer Dude Rosenberger - finished 3rd, Jenn Lyon - 4th place, Coby Archa - finished 9th.
From Survivor 11: Guatemala: Fishmonger Lydia Morales - finished 4th, doorman Judd Sergeant IV - finished 6th, Gary Ex-Dallas Cowboy Hogeboom - finished 7th.
From Survivor 12: Panama: Terry Dietz - finished 3rd, Cirie Fields - finished 4th, Shane Powers - finished 5th. (Please let Shane not be there, I beg of you!)
From Survivor 13: Cook Islands: Ozzy Lusth (yay!) - finished 2nd, Parvati Shallow (boo) - finished 6th, Jonathan Penner - finished 7th.
From Survivor 14: Fiji: Yau-Man Chan (but I knew that) - finished 4th, Michelle Yi - finished 10th.
From Survivor 15: China: Courtney Yates (don't yell at me, I'm just the messenger) and James Clement.
I can't remember Parvati. Courtney
Yau Man, Eliza, Lydia.