I was wondering the same thing. I know for a while Sprint was offering free activation if you ordered through their website but I have not seen anything on the iPhone 5. Im still in limbo on preordering through Apple or Sprint. I guess I will just see at 12:01.
The promotion waiving the activation fee if the device was purchased through the web site has ended. preorder time is 12:01 Pacific time that would be 3:01 EST 2:01 CST and 1:01 MST. Does make a difference where you live