I have beaten GTA IV for Xbox 360 more than a year ago. The most difficult part is realizing that most (if not all) of the missions involve either shooting up peeps, chasing another peep in a car, or both. There's simply no variety to speak of, and the side missions are a bunch of crap. Shooting darts? Bowling? Watch "TV"? Where's the taxi, vigilante, and ambulance side-missions? I think apart from the driving and shooting, GTA IV is devoid of all of the fun things that made up the GTA series.
Rockstar Games, I don't give a damn scripted relationships. I don't give a damn about your parodies of TV and the Internet. I don't give a damn about how supposedly "alive" Liberty City is. You want to know why? Because in the end, it's not actually very interactive at all. I want more of what makes a game a fucking game and not a fucking movie!
But the blood spattering on the hood of your car when you run over a pedestrian was a nice touch. And the physics are a lot better than in the older games. But GTA IV could have been so much more if Rockstar didn't have their heads up their asses about so-called "realism".
And I'm not about to go back to glitchy, ugly, old San Andreas. I'll be looking forward to Saint's Row 3, the REAL future of the GTA series.
Oh, and San Andreas and IV were quite easy for me, even though I suck at most video games.