Google's EMail as WebFinger

Google enabled the next generation of the UNIX like finger command - WebFinger - for all Gmail accounts. WebFinger provides users with a standardized and decentralized way of sharing their profile and identity information online
Google  announced that the company has now enabled WebFinger fall all Google accounts with public profiles.
Making Your Email Address More Useful
You can think of WebFinger as an email-centric cousin of OpenID. While OpenID associates your identity with a URL, WebFinger links your identity to your email address. WebFinger can store metadata about your account and make it publicly accessible. This data can include your public profile data, information about other services that are used by this email address, a URL to your avatar, or - if you choose so - a declaration that this address doesn't have any metadata associated with it. The WebFinger metadata can also point to an alternative identity provider, which can be an OpenID server.
Currently, there are not a lot of user-facing projects that expose this data, but you can find a small demo service written by Google engineer DeWitt Clinton here.
Adding Value to Google Profiles
With Buzz, Google already put a lot of emphasis on Google Profiles and today's announcement increases the value of these profiles even more. It's important to note, though, that WebFinger is an open and free protocol, so any email service and identity provider can implement it. You can find more detailed information about the WebFinger protocol here.