Google Icons on Google+ has posted about a brand new favicon that Google has uploaded on their servers.
This one is named google_favicon_128.png which is a solid indication that it would become the new default favicon on Google.com.
Google currently uses a multicolored favicon on their homepage. This new icon is bland with a dual color design.
Google has been simplifying their icons across their entire service range. We have already seen Google Plus logo and icon changing. Google Docs etc. are also getting brand new icons.