See the full post for more Windows 7 analysis
Looking ahead to the finish line, Sinofksy declined to provide a schedule for Windows 7, though my sources tell me it could arrive as soon as mid-2009, or about a year before Microsoft's vague public pronouncements. He said that the build released at PDC was an M3, or "milestone 3" build of the product and that that would be followed by a beta release. Sometime in that timeframe, there will be a fairly public beta--"everyone will be able to sign up and get it," Sinofsky noted--and then the release candidate (RC) phase. "These will be very visible milestones," he said, "and each step informs the next. There's no point in a guessing game for the schedule. It's a promise and deliver schedule."