Rockstar!!! why no GTA 4 for PC?

I'm disappointed to say the least.
It appears that Rockstar http://en.wikipedia.org/wiki/Rock_Star has no intentions of releasing GTA4 PC.
IS the code for the X-Box 360 really so much different that they cannot code for both the X-Box 360, and the PC simultaneously using the same code?
If they can then whats going on?
Did Rockstar make a deal with Microsoft and Sony to make the game exclusive to only those two platforms, and if so wouldn't that limit their sales, considering all the loyal GTA PC gamers?
I know I am very unhappy considering GTA is one of my favorite game titles of all time.
Do they plan to port the game to PC at a later date, if so how long do we have to wait?
If they do not release it on PC then I guess my days of lawlessness, disorder and chaos are over, because Although I love gaming I refuse to buy a console, I am a PC guy through and through.
Sad are the days without GTA.

Sincerely
A disgruntled gamer.