As he kicked off the Microsoft Build Developers Conference, Microsoft CEO Steve Ballmer , revealed that in the three days since Windows 8 has been available to the public it has sold over 4 million copies of the upgrade.

Another tidbit he offered about the conference itself was the level of interest which was reflected in the fact that it sold out in just 53 minutes when registration became available earlier this year.

He indicated that this is individual sales via download and also store stock based sales.  He added that 10’s of millions of licenses for Windows 8 have also been sold to corporate customers but they are not under any specific timetable to install those licenses.

He also used some quotes from partners, retailers and websites about the new OS:

  • “Customers are excited to try out the new features and hardware” Mike Edwards, Staples
  • “Sales of laptops during launch weekend have been 20% ahead of our forecasts” Mark Slater, Dixons Retail Ltd
  • “We are excited about what we are seeing from initial sales and it looks good” John Solomon, HP
  • “Microsoft Surface is hot” CNET
  • “10 reasons to embrace Windows 8 now”
  • “Windows 8 to bridge gap between PC, mobile devices” Associated Press
  • “Who would have thought that in 2012 Microsoft would be the company with the boldest phone and software design?” @JoshuaTopolsky from The Verge

A very good start to the new ecosystem of Windows 8, Windows Phone 8 and Surface.