PDC08 is scheduled for October 27-30, 2008 at the Los Angeles Convention Center. There will be a pre-conference day on the 26th. From the announcement I got...

PDC is the definitive Microsoft event for software developers and architects focused on the future of the Microsoft platform. Mark your calendars and save the date. More information coming soon.

http://msdn.microsoft.com/pdc2008

Read the complete post at http://www.grokdev.com/Blogs/scott/2007/12/07/PDC2008Scheduled.aspx