The short answer to this question is no. Whilst there is always room for improvement in a game, you just can't fault R* for their choices in developing this game no matter how hard you try. The lead character Niko Belic is arguably the greatest protagonist a computer game's ever had. People naturally point to the actual character himself as a way of justifying this type of praise, but equal credit for this fantastic character goes to the actual depth of the game itself. Niko has been - as with EVERYTHING else in this game - generously fleshed out. Its not just that he's such a cool guy, which he is, its that he says so much, he does so much, he's involved in so much. Everyone knows the main thing wrong in previous GTA games was some aspects of the gameplay which were incredibly simple and outdated. Its all very well flying a harrier,mowing cops down with a combine harvester or owning a scarface type mansion. But the simple things like shooting and driving in the previous GTA games were, well, a little lacking to say the least. Half the time there was no rhyme nor reason to your death, other than bad luck because of the aiming system. With GTAIV however, both the driving and the shooting has had a complete overhaul - you are in complete control. The cars are alot more realistic which will put off some of the lesser skilled gamers - go play tetris for the rest of your life if you can't adapt to it I say! The shooting in the game has taken heed from titles such as Gears of War in that it employs a cover system so that you can judge when to shoot the enemy depending on a number of factors. Both these areas of development improve the game immersurably & add some much needed substance to the franchise.
Also, you now have a customisable mobile phone which you are free to use to contact anyone you've phoned throughout the game, this is useful in so many ways, mostly for arranging leisure activities such as shooting pool, bowling, going to a strip club or taking one of your many girlfriends out for a meal. Taking your friends and associates out gifts Niko with different assets depending on the NPC, these range from a colleague who'll meet you anywhere at anytime to sell you guns, to a girlfriend who will help get the cops off your back in those more lairy GTA moments. The leisure side of things is a welcome relief from the constant slog of doing missions, its nice to inwind & go watch a comedy show or play some pool from time to time - or why not go home and watch tv in your safehouse? Thats right - you can watch tv too!
The missions are generally the same as the GTA games before, although they do seem more original than they actually are due to the new shooting/driving system. Lastly i'll mention the quality of the other characters in the game. I've never seen a cast of characters like this in a game, or anywhere close. Almost as commendable as the improved gameplay is the dialogue & characterisation. You will really feel like you're taking part in a (top quality) hollywood picture on more than one occasion, due in no small part to the superb scriptwriting.
The only negative thoughts i've dared conjour up during my GTAIV experience so far has been, "what have I done to deserve this fantastic game" & "I almost don't want to play anymore as it will make the game end sooner". It really is just too much, and too good.