New stuff is discovered for Core War fairly often, although the basic paper / scissors / stone strategy remains the same. A tournament sounds like a good idea, there hasn't been one for a while.

It should be noted it's more of a league where each round occurs once a week and the scores are only valid for that week. You could of course keep track of the long-term progress of your warrior too but they're not ranked for boasting purposes. The aim is to encourage newer players to the game, as much of the folks on neverfear IRC (myself included) are.