Well, it seems like the DRM thing is the least of GTA 4's problems.
You've got to say it's a pretty poor effort to ship a game in a state like this. Broken or non-existent textures, insanely prohibitive hardware requirements, compulsory add-on software that is seemingly incompatible with the actual game itself and the fact that the release code actually appears to be in a much worse state than the review code that was sent out... I'm staying well clear of this heap of badly optimised code. (And that's me being nice about it)
I'd say it's all part of an elaborate plot to make us all stop playing games on PCs and buy consoles, but I don't credit Microsoft with that much intelligence. And let's be honest, it would be a really fucking stupid way of going about it, too.