How long ago did you buy the case? I have the 100r, I believe it has the same power button design.
EDIT: The 200r like my 100r has a 2 year warranty. If it is in fact a dead switch and your case is less then 2 years old Corsair could offer to repair/replace it or send you a new front panel. If your case was purchased more then 2 years ago you might be able to contact corsair and buy the front panel.
I don't believe the switch is user replaceable.
EDIT AGAIN: The switch might be separate from the front panel, can't tell from the pictures.