Windows 8.1 Update has barely been available for a week, but installing it is soon going to be essential if you're already running Windows 8.1. From 13 May, Microsoft will stop offering security updates for consumers running a non-Update version Windows 8.1, while enterprise customers using Windows Server Update Services will be cut off from 12 August.
Microsoft announced the changes in a blog post from senior consultant Steve Thomas. The same update restrictions will also apply to Windows Server 2012 R2 Update. Initially Microsoft had planned to enforce the May cut-off date (which coincides with Patch Tuesday) for enterprise customers as well, but extended the deadline after customers complained.
Given Microsoft's current plan to provide annual updates to its desktop and server OSes, it's not entirely surprising that it's trying to encourage adoption. That said, it's somewhat odd that users of older Windows 8 and Server 2012 systems will continue to receive security patches.