Gmail, Google Now and Google Calendar collide - welcome to inbox

My main hope is this will improve the management and workflow of emails, plus calendar which has become invaluable to organizing my day to day things.

Meet your new inbox.
Built on everything that we've learned from Gmail, Inbox is a fresh start that goes beyond email to help you get back to what matters.  Note, like the original Gmail, it is invite only at the moment.

Review from The Next Web
Review from The Week

Main web site: http://www.google.com/intl/en-GB/inbox/