My impression is that Pwn2Own skews hard towards Safari for two reasons: the Air that's normally a prize is more desireable than the random cruddy Windows lapto

My impression is that Pwn2Own skews hard towards Safari for two reasons: the Air that's normally a prize is more desireable than the random cruddy Windows laptop, and Flash is a much softer security target than Safari itself, so that's usually what gets exploited.