Source -Windows 7 was released to manufacturing on July 22nd, 2009, along with Windows Server 2008 R2, and both platforms made it to customers by October 22nd, 2009, with the client flavor of the OS being the last to reach the general availability stage. Undoubtedly, for the latest iterations of the client and server operating systems, the Redmond company will produce the first service pack come next year. There might even be a third service pack for Windows Vista, although Microsoft is keeping all details under a hermetically shut lid. But one thing is certain, as 2010 rolls in, Microsoft will shift its focus to Windows 8, the next generation of Windows.
Users are bound not to come across publicly shared details on Windows 8 from Microsoft for quite some time. Going out on a limb, I would say that the software giant will start unveiling the first Win8 information through official channels no sooner than the end of 2010, or even in 2011. After all, Jon DeVaan, senior vice president, Windows Core Operating System Division, and Steven Sinofsky, president, Windows and Windows Live Division, kicked off the Windows 7 engineering conversation with the public in August 2008, a year and a half after Vistaâ??s GA in January 2007.
http://news.softpedia.com/news/Windows-8-Coming-into-Focus-in-2010-128959.shtml