AusGamers has reviewed GTA IV in a super-constructive article that reads more like an essay. In the review they point out the lack of dynamic affect on the overall narrative based on actions performed while free in the game's sandbox world.
From the review:
"Like the aforementioned games, GTA IV comes *close* to perfection. Subjectively, it's a matter of time and placement, really. At the end of the day the amount of time and effort injected into every facet of all of GTA IV's features could be considered "perfect", but like so many "perfect" field representations, it's still going to be looked at as a product of its time. This is truer most on the tech side of things. For a moment, let's forget the brilliant scripting, do away with the overtly tongue-in-cheek radio, television and advertising social commentary. Let's ignore the game's scope in geometry and freedom, we'll overlook the near-perfect city planning and deliberate visual design inconsistencies for added realism, and break the game down to its two most fundamental parts: Narrative and choice."