http://www.realityblurred.com/realitytv/archives/survivor_21/2010_Jan_05_future_plansIf what this article says is true, Survivor might air one All-Star season per year, both to save money and to make sure that everyone actually has a personality.
I personally like seeing new cast members every season, and think that this setup is too MTV-ish. Besides, I don't think I'll be able to handle the Coach & Russell show for 14 weeks every year.