How the 8.1 Preview Update Will Be Installed

Mary Jo Foley at ZDnet has a good article up about how the update will be delivered:

Key points:

When the 8.1 preview is available, Windows 8 and Windows RT users will receive a Windows Update notification. That update will trigger the new bits to show up in the Windows Store, where potential testers will be able to read the description and choose whether or not to install. Once the final versions of Windows 8.1 are available, after their release to manufacturing, those who have downloaded the preview will get the same Windows Update plus Windows Store notification. While their data and accounts will be preserved if and when they choose to install the free, final 8.1 release, all their apps must be reinstalled,

http://www.zdnet.com/microsoft-goes-public-with-windows-8-1-upgrade-policies-7000016419/