UPDATE: Google has changed the default behavior, removing the background picture. Hopefully it stays as a user controllable option.
Google allows you to replace the picture with your own and I created a white background, but it doesn’t look right since the Google letters are still white.
I ended up settling on a black background which slowly fades in. It makes Google seem slow to load. At least I’m able to search Google through the search box on Safari.
Here’s an image of a black background that you can use. Just click to enlarge and then save it to upload to Google.