With 260 million Gmail users worldwide , it’s obvious why Google allows email to be used in verifying authors of content; to increase the produce of social search annotations.
Today Google announced that authors can claim content via email. Simply link your email address from content you’ve authored and verify that email account via your Google+ profile.
I think verifying authorship via email is an ace card from Google and its efforts in social search.
Tapping into 260 Million Users
When you start too frequently (more than trice ) send or receive emails in Gmail from an email address, Google automatically adds that person/address to your Gmail (or Google Talk) contacts.
In Google’s description of social search, it reveals that users are subject to social search results from users in your Gmail (or Google Talk) chat list, amongst other sources.
Putting the pieces together, opening up email to allow users to liaise with authors of claimed content via email, preferably Gmail for Google, expands social search annotations by the potential of 260 million in one swift move – the ace card.
Meaning, whether communication by via email, Google+ or public social networks like Twitter – Google will be able to socially annotate the websites you visit, talk about, share and discuss with your social connections – privately, of course. There is a different between public and private connections.
Private: Private social connections, like your Google chat list and Google contacts, are not public on the web. If you and Adam are chat buddies, we won’t share this information with any other users. You cannot see Adam’s other chat buddies or Google contacts, and he can’t see yours. However, if you are connected to some of Adam’s other chat buddies through other public networks, they may still appear as social connections. Google
Behind Closed Doors
I think email is the easiest and most commonly used medium to connect. With Google knowing who’s connected and by what manner via Gmail enables the search engine to gather more signals, for which it can then factor those signals into its social search results. Historically that’s been possible with Google Buzz and Talk, raising eyebrows, but comparing Buzz and Talk’s user numbers to Gmail, and it’s clear Gmail dwarfs both with ease.
Find out who you are connected to via Google’s connection tool. You need to be logged in.
What’s Next In Store
Google’s infiltrated your social networks, Google account, Gmail, search history – what’s next for social search and people signals?
Remember, it is Internet protocol to link and human nature to want to share.
 Wikipedia: Gmail – http://en.wikipedia.org/wiki/Gmail
 Guestimation. Anyone clarify?