Why Google Changed Their Favicon.

The Official Google Blog explains the reasons behind changing the favicon, it also states that the icon were are seeing right now is infact not the final version. and people can even send in their ideas, feedback and suggestions:

You may have noticed that Google has a new favicon, the small icon you see in your browser next to the URL or in your bookmarks list. Some people have wondered why we changed our favicon — after all, we hadn’t in 8.5 years(!). The reason is that we wanted to develop a set of icons that would scale better to some new platforms like the iPhone and other mobile devices. So the new favicon is one of those, but we’ve also developed a group of logo-based icons that all hang together as a unified set. Here’s the full set:

The design process we went through was rigorous and interesting, so we thought we would share more of it here. We tried in total more than 300 permutations. It was much harder than we thought at first. We wanted something distinctive and noticeable, so we aimed toward transparency or semi-transparency, so the image would have a more distinctive noticeable shape than just a block. We wanted something that embraced the colorfulness of the logo, yet wouldn’t date itself. Since we don’t really have a symbol that means Google, we felt it best to work with the logo and letters within it. Our design team tried literally hundreds of approaches. You can see some of our explorations here.

By no means is the one you’re seeing our favicon final; it was a first step to a more
unified set of icons. However, we really value feedback from users and want to hear your ideas that we may have missed. If you have your own notions about the Google favicon, please send them to us. We’ll do our best to work them in, and maybe your idea will be the one that people see billions of times per day.

[source:google blog]