My final assessment, after finishing the story and ~85 hours playtime:
- The story is great at the beginning and into the middle, but once you get to Jersey and involved with the Italians it falls completely apart and becomes the same-old mobster game. Niko, Brucie, Packie, Florian, etc. are fantastic, distinct characters which will stick with me for a long time, but I couldn't name any of the Italians they all just blur together.
- Just screwing around and causing chaos is NO FUN in this game. That's all I did in the previous games, but something about this one doesn't click. Even with the addition of free mode online I can't keep interested. Perhaps because it's so realistic / not arcadey... which leads me to...
GTA4 is the Real Driving Simulator (tm) !!!
I'm completely and totally addicted to just cruising around in the game with the flow of traffic following the rules, chilling to the radio, soaking in the sights and being 'seen'!
I love cars, but I've never liked driving games AT ALL because I don't like racing. Gran Turismo (etc) give you these BEAUTIFUL cars and then force you to race them around sterile tracks: WHAT A BORING WASTE! I just want to CRUISE!!! GTA4 lets me do that!
It's quite challenging, particularly in the big American barges, to keep with the flow of traffic and drive smoothly without your shocks going crazy (and spilling your imaginary drink!). There are a few annoying quirks (why do the AI drivers change lanes for no reason constantly!), but I think GTA is at its best when you follow the rules!
edit -- I love how Algonquin is full of one-way streets and various rare/complicated intersection types which normally confuse/scare the hell out of a small town boy like me (from a place where all corners are 45* and every street goes both ways). All the road markers, signs, lights, etc. work the way they should so it's a great way to learn to manage big city driving!!!