Inspired by Ask.com's themes and Bing's wallpapers, Google will allow users to add a background image to the Google homepage. "We're introducing a new feature that brings a whole new level of personalization to Google by letting you add a favorite photo or image to the background of the Google homepage. You can choose a photo from your computer, your own Picasa Web Album or a public gallery hosted by Picasa which includes a selection of beautiful photos," explains Marissa Mayer.
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Google says that the new feature will be gradually released in the US and it will soon be available outside US. A lot of people use Google as their homepage and many would like to customize the homepage. I'm not sure it's a good idea to add visual clutter to the Google homepage and to make it load slower, but iGoogle, Bing and Ask.com have a lot of happy users.
Tip: to see other customized Google homepages, check the #mygooglepage Twitter hashtag.