I first read about this on Lifehacker. Google now lets you choose a theme for your Google homepage. The neat thing is that I picked the Tea House theme which has a skyline in the background. When I chose the theme, it asked me for where I lived so it could make the skyline match that of my home town. Pretty nifty 
These are the kinds of things that really aren’t necessary, but adds that little bit of extra oomph to the experience.
[update]skyline = sky coloring to the time of day (bright or dark) [/update]
Does it actually match the skyline with the city in which one lives? I thought it just matched the *coloring* to the time of day where you are to simulate things like sunrise and sunset.
You are right - I meant that kind of skyline
I guess I just used the wrong word. At 5am this morning my Google Homepage had a dark sky and now it has a sunny sky.
How do I change my location to another place?
Click Select Theme again and it will ask you if it has the right location after you save it.