It was just a matter of time until Google would release time travelling. Now you can go back in time when visiting a location to see what the area looked like a few years back. Google Street View started in 2007 in a few select cities in the US. Images have been updated a couple of times since then in most locations.
If you see a clock icon in the upper left-hand portion of a Street View image, click on it and move the slider through time and select a thumbnail to see that same place in previous years or seasons. (source: Google Lat Long)
In some parts of New York there are 8 different times to choose from, but in most places I guess it’s fewer than 4.