The Pre-Betas delivered at PDC and WinHEC 2008 are timebombed to expire in January 2009
"Work continues on the development of Windows Vista's successor, Windows 7, and the operating system has managed to jump a few build numbers from the end of October 2008. At the Professional Developers Conference 2008 in Los Angeles, Microsoft served Windows 7 pre-Beta Build 6801 to participants, while demonstrations already featured Build 6936. However, since that point in time, the company has also evolved past the Windows 7 M3 Build 6936 showcase bits.
Windows 7 pre-Beta 6948 is already being tested, as Microsoft is making its way to the first fully fledged Beta of the operating system. Senior Vice President, Windows and Windows Live Engineering Group, Steven Sinofsky, has already revealed that the Beta version of Windows 7 is planned for the start of 2009. In fact, the pre-Beta M3 bits delivered at PDC 2008 and WinHEC 2008 are time-bombed, and set to expire in January 2009. The expiration date remains in place independent of the slmgr method to prolong the initial grace period of Windows 7 Build 6901, or using valid or leaked product keys to activate the bits, or one of the cracks that have started to circulate."
Read More :- Windows 7 Build 6936 and 6948 on Windows 23rd Anniversary - KezNews.com