At the Microsoft Developer Forum, in Tokyo, Japan on May 23, 2011, Microsoft's CEO Steve Ballmer talked about the future of the operating system, including references to Windows 8. He estimates that in excess of 350 million Windows 7 PCs will be sold by the end of 2011 alone.
Taking into consideration the 350 million Windows 7 PCs units expected to ship this year, it's quite easy to do the math when it comes down to the total number of operating system licenses sold by the start of 2012.
In April 2011, the software giant revealed that sales of Windows 7 had surpassed the 350 million units mark in just 18 months after launch.
It's clear that the current adoption pace of Vista's successor has prompted Ballmer to offer the very optimistic forecast of a total of 350 million Windows 7 PC units sold by the end of the year.
Since sales of previous Windows clients, including Vista and XP have been discontinued, OEMs are only selling Windows 7 machines, and will continue to do so throughout 2011.
Historically, Microsoft sells the vast majority of Windows licenses on new OEM machines, which represent over 80% of the Windows Division's revenue.
This means that actual sales of Windows 7 licenses will in fact be higher than the actual number of PC units sold, since the software giant will also push upgrade and retail copies of the operating system.
Back in January 2011, the Redmond company had revealed sales of 300 million Windows 7 licenses.
With another 350 million or more copies expected to ship by the end of 2011 on new PCs, Windows 7 might just pass the 650 million sold licenses ahead of 2012.