Right now, the system is used as an identifier so people know what sort of game you're looking to run. It also affects the LFG settings, which allows players to get an email when a game they're looking for gets created. I've been considering how I want the game system to affect the forums; it's a tough decision to make. Eventually, I'll have the character sheets more closely integrated with the forums, such as the ability to make roll straight off your character sheet. With systems, however, it's tougher to say, as people run games differently, and being too limiting would be bad for game hacks. That said, I'll end up making general tools you can add on to any game, regardless of system.
