Really? Yes! Customers running Windows 7, Windows 8.1 and Windows Phone 8.1 will be able to upgrade for free within the first year of Windows 10 after launch.
Additionally, Microsoft will keep all windows 10 devices up-to-date for the supported lifetime of the device, with no cost. The idea is to provide new features as they become available without waiting for the next major release.
Microsoft will launch Windows 10 later this year.