I feel like i could reply to half the top level posts with this link:
http://blogs.windows.com/business/2015/01/30/windows-10-for-...
>January 30, 2015
> this is much more than a one-time upgrade: once a Windows device is upgraded to Windows 10, we will continue to keep it current via Windows Update for the supported lifetime of the device – at no cost.
>We think of this as Windows as a Service
>we are introducing a new approach for business customers, which we are referring to as the Current branch for Business. By putting devices on the Current branch for Business, enterprises will be able to receive feature updates after their quality and application compatibility has been assessed in the consumer market, while continuing to receive security updates on a regular basis. This gives IT departments’ time to start validating updates in their environments the day changes are shipped broadly to consumers, or in some cases earlier, if they have users enrolled in the Windows Insider Program.
>Based on what we are hearing from customers, we expect most will take a mixed approach in how they keep their Windows 10 systems up to date. They will likely target a different pace of updates for different users and systems, depending on the specific business needs of each group.
etc.