[imtringued]

Just because something uses a grid doesn't mean it's a cellular automaton. You can probably write DF as a cellular automaton but that's probably not what happened.

If dwarfs have x,y coordinates that mark their position and the coordinates are changed when they move then it would not be a cellular automaton.

A cellular automaton would take a cell and look at surrounding cells to see if there is a dwarf that wants to move to the currently processed cell and switch the current cell to a new dwarf cell. The dwarf cell would see that the dwarf can successfully move and delete the dwarf cell.

Which method do you think is DF using?

[rhn_mk1]

I think individual dwarves could still be modeled as cells, if there was an additional layer (or a single cell?) holding their future actions.

The automaton would lose the nice property of being spatially isomorphic to the screen, and the possible states would explode, but if my understanding is correct, it could still be a cellular automaton.