A mapping committee is not really necessary to start an annual mapping competition or the such.... All it needs is a few people willing to set rules and regulations, and get it started (just like the heads of PBCup did). If there's a big competition made with a good number of mappers involved, it would be easy to create a sub-forum for the contest(s) (just like the PBCup sub-forum). But I don't get a special sub-forum just for a "map committee", that only they can talk in. PBCup didn't require this. If you need a special place to chat for people to create a map competition, IRC channels can be made, PM's can be done, etc.
I'm not condoning any of ya'll's ideas, I just don't think a map committee is necessary for any of them to get started. You can start tomorrow easily. Just a few of you need to get together and think of a competition, and the rules for it... Once its ready all you have to do is post the competition, and the rest usually takes care of itself.