One thing that has been said on this forum before but not in this thread: the people who post here are a very biased sample of computer gamers. Most gamers would find Dwarf Fortress literally unplayable. Many of you might be fine with the current interface, but that's because you wouldn't be here unless you were one of the few people who find it at all usable. Heck, I program using emacs in a terminal and I had a very hard time getting into this game.
It shouldn't even need to be said: Toady One doesn't owe me anything. He's certainly free to take Dwarf Fortress in whatever direction he chooses. However, that direction looks to me like a dead end, one where improving gameplay and fixing bugs is not as important is introducing new, buggy levels of simulation that would be completely invisible and irrelevant if they were working correctly. That's too bad, because I think the sort of gameplay pioneered in Dwarf Fortress has a lot of potential. So much potential, in fact, that even I've tinkered with my own implementation of certain Dwarf Fortress features; after all, if Toady One isn't planning to make this game the game I want it to be (again, a choice he has every right to make) then that becomes up to me and like-minded people.
I don't like the attitude that Impaler has shown, but I think his ideas about game development are the right ones. Chances are he won't go through with creating a fully functional game, since that's very hard, but I've offered him what code I have (an implementation of fluid dynamics). Ban me if you will...