Minecraft requires a really good system right now, it must be the least optimized game of all time. I also think it's really not a game for everybody. You must be a really creative person to like such a sandbox game, where you start with nothing, and don't know nothing until you a) try things or b) read the wiki. In that way, it's quite like lfs : the learning curve is steep at first. IMO a driving simulator could be quite popular, maybe more than minecraft (after all, who deosn't drive?) if it could be used without an expensive, always broken, space-consuming driving wheel.
Oh, and about the servers, minecraft now runs ons Amazon S3 servers, and I've heard they're pretty cheap.
Nyway, I don't want to bash LFS, it's a great game. Only wanted to straighten up some things about minecraft.