In an entry on the official Windows blog, Terry Myerson, Microsoft’s Executive VP for Operating Systems, wrote:
“We continue to make great development progress and shared today that Windows 10 will be available this summer in 190 countries and 111 languages.”
Initial speculation had suggested that Windows 10 would be released towards the end of the year, but this new announcement indicates that it will be available significantly earlier, during the summer months of June to September.
It was previously announced that Windows 10 would be a free upgrade for users of Windows 7 and 8.1 for a year after its release. Current testers of the Windows 10 Technical Preview should be able to upgrade straight to the RTM release version without a clean install, as Windows Insiders chief Gabriel Aul indicated in a tweet last December.