If you have already installed the Windows 8 Developer Preview build on your PC, you may or may not be aware that the build was supposed to expire on March 11, 2012. Similarly, the Windows 8 Server Developer Preview version was scheduled to expire on April 8, 2012. Now Microsoft has quietly released an update for both of those builds that gives folks a lot more time to use them
While the actual download is handled via the Microsoft Update feature in Windows 8, Microsoft has posted up a web page explaining the upgrade. When the update is installed, both the Developer Preview versions of Windows 8 and Windows 8 Server will have their expiration dates extended until January 15, 2013.
Once the Developer Preview version does reach its expiration date, Windows 8 will send messages to the user saying it will restart Windows every hour until a new product activation key is entered.
It's currently unknown why Microsoft would go ahead and extend the Developer Preview version of Windows 8, especially since the company has already announced it plans to launch the Windows 8 Consumer Preview version on February 29.
Thanks to venkat for the heads-up and it is posted over at techdows.com too