Get Innocuous!

This is the commercial they are running in Europe for GTA IV. I think it does a great job of showing off how alive Liberty City is. It shows that while Niko is a part of the city, he isn't what makes it go. Liberty City isn't lying in wait for whatever Niko does next, instead it goes about its daily life. While Niko can change what happens in a given day, he doesn't have to do a single thing in order for things to happen in the city.