It only took Steve Ballmer about 10 minutes of being on stage during the opening Build 2013 Keynote to announce that the Windows 8.1 Preview was available for download.
There are a few options to get it.
You can head to preview.windows.com and download the update for your x86/x64 and RT Windows 8 devices. You will be prompted to grab a stand alone Windows Update install to ready your system. When that update is installed and your device reboots you will get an immediate prompt to head into the Windows Store and download the entire update.
On my Surface RT that update weighed in at 2.2GB.
If you are a TechNet or MSDN subscriber the ISO’s are already there waiting for download and installation. By the way, those ISO’s are only for X86 and X64 systems – no RT ISO’s. The only way to update your Surface RT or Windows RT device is through the update process that you can start at preview.windows.com.
This is a preview and not the final bits so there are consequences to using it now as it relates to apps, data, etc.
Play it safe and backup your device first then read the Windows 8.1 FAQ.
More to follow.