There have been a few contributions to TOL by other people but it's still basically just me working on the game, and currently I can't dedicate as much time to the project as I'd like. I agree with @buckmaster about the inherent problems of a community-developed game (especially if it isn't a straight up clone of something that already exists). On the other hand one of the ideas of TOL is that the same client can be used to play potentially wildly different games (for example: if you wanted to make a multiplayer game that's playable using the TOL client, you "just" have to get the required art and client-side scripts into http://content.terminal-overload.org and (if they exist) engine modifications merged into https://github.com/fr1tz/terminal-overload).
