GTA 3 was fun, specially going to my friends house and doing some of the missions. Then I bought it for PC and beat it all the way through and stopped playing it...there wasn't much left, unless you want to spend the rest of the time looking for hidden packages, which I hate doing in games. So I was left with no replay value, although the time I spent was enjoyable.
Then I got Vice City, and to tell you the truth, there was nothing innovative in that at all. The whole "chainsaw" or "walking into buildings" or "motorcycles" was just a pathetic gimmick to sell games. Unfortunately, Americans are pretty "stupid" when it comes to how innovative a game is, and they swallowed up Vice City whole. I took a poll of my friends of how quick they stopped playing, and it was right after they completed the missions. It wasn't like GTA III, where they played for an additional few months just enjoying the "free-ness" in the game.
So in conclusion, GTA III was very innovative. Vice City, just a rehash, as some people like to call it.