With the public preview of Windows 8.1 gearing up to launch on June 26, Microsoft is now talking about how this "demo" will work for current Windows 8 customers. The process was actually covered in a session during TechEd North America on June 4 entitled "Windows RT in the Enterprise", and relayed by ZDNet.
Microsoft Senior Product Marketing Manager Michael Niehaus explained that when the preview becomes available, Windows 8 and Windows RT users will receive a Windows Update notification. Once the preview OS is installed, new related apps will appear in the Windows Store, allowing potential testers to read the description and choose to install or not install.
When the final RTM versions of Windows 8.1 and RT 8.1 are finally launched, customers who already downloaded and installed the preview will get the same Windows Update plus a Windows Store notification. Data and accounts will be preserved if and when customers choose to install the final, free 8.1 release. However the "preview" apps must be reinstalled with the RTM versions.
Niehaus added that customers who decide to roll their devices back to Windows 8 after installing the preview will still need to reinstall the apps once they move to Windows 8.1 RTM. The apps in question depend on the version of Windows 8 (x86 vs ARM). For Windows RT devices, the Windows Store/Metro-Style preview apps will need to be replaced. On x86-based Windows systems, both Windows Store/Metro-Style and Desktop apps will need to be reinstalled.
A Microsoft official added that customers who do not participate in the public preview – those that opt to wait until Windows 8.1 and RT 8.1 are released – will not be required to reinstall their apps, as all data, settings and apps will carry over to the updated platform. There's also no deadline in updating to the next version either, meaning customers can do so at launch, later down the road, or not at all.
Microsoft has reportedly been working on the overall footprint size of Windows 8.1 compared to Windows 8, removing old components, temporary files and improving NTFS compression to free up disk space. The preview build will require 4 GB of free space to install, and will not replace the recovery partition of Windows 8, even if it has been deleted.