@mention in Outlook email is a great new feature to help you manage your email more efficiently . Now you can quickly refer to colleagues in your email, helping to get their attention and let them know that they are being specifically referred to. Anybody @mentioned in the email will be highlighted in blue. Also, if they are not already part of the email conversation, they will be added to the To… list. This is part of a package of updates that will also improve how Clutter is handled.