This new personalization feature would focus on content such as orders, tickets, reservations and events. For example, if a user searched for "my flights," Google would pull flight reservations from their Gmail messages. This would only work for logged-in users that are receiving personalized results.
Google explained, “you can now search for [my purchases] to see a list of recent online purchases from select merchants and track the packages to see if they’ve arrived yet.”
The search results page would become a multi-purpose page--largely extending the scope and potential of a search engine. Whether or not Google gets it right with this Gmail to Google search expansion, it is very clear that the future of search involves personal content and not just public sources.
This field experiment by Google shows the general direction of search in the future, we feel. The content and design of search will be changing rapidly as it competes with Facebook and sees new potential with mobile. The mission of search engines like Bing and Google will be to find greater relevance for users with search, and this will require ongoing experiments with design, content and delivery of search tools--and there inclusion in other web and mobile applications. We see the bud of something quite powerful here.