Google email users who store any of their personal information in their accounts should be very concerned, a Google engineer confirmed today that approximately 20 million accounts have been hacked, allowing for user information to be gathered.
Along with basic login details, hackers have also compiled a list of users whereabouts through the use of Google IP tracking and stored encrypted cookies.
Also affected are free and corporate accounts from Google Apps for Domains.
Google engineers are urging Gmail users to change their password as often as possible (at least every few hours) over the next several days until the direct cause of the hack can be discovered.
U.S. and EU officials are investigating the breach and are expected to release their own findings in the next five to six months.