The indie blog MSFTKitchen today posted a link to a Microsoft job post – for a role entitled “Software Development Engineer-BING” - that directly mentions Windows 9 and Internet Explorer 11:
The team will be constantly delivering great products in areas including Windows 9, IE11 services integration, touch friendly devices including iPad and more.
According to NeoWin, a LinkedIn profile that can be found here contains a mention of Windows Phone 9. Given the progression of Microsoft from Windows 7 and Windows Phone 7 to Windows 8 and Windows Phone 8, to see the company slip right forward to Windows 9 and Windows Phone 9 is simply logical.
Windows 9 is anticipated to be Microsoft's next-generation operating system, while a Windows 8 update called Blue is expected later this year.