I believe you can actually bribe Massman to tell you rules in advance!
I recall a picture from GOOC 2010 of him receiving bribe - and he was fairly cheap to pay off! :D
Jokes aside; Nah dont know how it does these days, but a year back, Massman was the mastermind of the competitions, he made the rules himself, and is fairly good at it - he is TERRIBLE at take critic, dont suggest anything could be done differently, I warn you.