I don´t quite get how one would want to play one of the best SP franchises on a PC. I have seen a few mods of GTA4 on youtube and they are all pointless stuff like an iron-man costume, a monster truck, replaced planes on the airport, a mod with a few other cars and all this pointless stuff.
It´s not like mods change the whole game and to be honest GTA has always been the perfect console game and it will stay that way. Also playing it with a mouse and keyboard is like trying to play an arcade racer with your mouse and keyboard.
PC ports of GTA are horrible anyway so I don´t get the guys that are waiting for a PC release instead of just buying the game on a console.