I think it a loss that a game with such original complexity has the most primitive graphics. Nobody wants 3D acceleration, but an upgrade to a simple 2D with sprites and effects with a better interface, would open it to a wider crowd.
The funny thing is, Dwarf Fortress is simulated in 3D. With the 3D viewer, you can even look at your terrain in 3D: http://i140.photobucket.com/albums/r21/khyron2k/Dwarves/Dwar... If DF would look like that during gameplay, I'd immediately start playing.
[1] Obvious nitpick: some players do indeed challenge themselves to build everything above ground.