Microsoft will unveil Windows 7 at PDC and provide developers and attendees with a pre-beta build of the operating system.  Steven Sinofsky, Senior Vice President, Windows and Windows Live Engineering Group, will keynote on Tuesday, October 28. Part of Sinofskys keynote will be a demonstration of the work being done for Windows 7. Advances across the full range of Windows - including the kernel, networking, hardware and devices, and user-interface will be demonstrated at PDC. Attendees of PDC will also be able to attend 21 different sessions based on Windows 7.