Google’s embarrassing move!
I still don’t understand the reasoning behind, but for some reason Google put up a background image in their home page. This would of course remind you of Bing that has this feature since day one. Google has now made this feature an option and you can choose any background from a link at the left bottom corner.
It is notable that Google has never put up any ads on their home page for speedy loads and sleek look, I like it as plain it has always been.
When you are already number 1 by a long shot why imitate? I am sure this would have left many Google executives with a red face. The picture below is an example of the custom background.

I am sure many must have liked it as a personalized experience.
– Sumit