[alexti]

I have serious doubt about anybody creating game which has great SP and MP in any foreseeable future. You can probably share graphics and story, but the gameplay would have to be written pretty much separately. The core differences are probably in turn structure and game depth. MP games can (and should) have strategic depth (like Dominions), in SP games strategic depth causes a serious problem, because writing AI that can deal with it is not within resources of game developers. Different turn structure means a lot of differences (scripted combat vs turn-based combat, order-based commands vs moves) etc... Of course, that means different balancing, and as result players will need different strategies in SP and MP which brings to the point of pretty much 2 different games under one title. And that I suppose doesn't make business sense, because if developers have expertise to build 2 great games they can just release them as a separate games.