WinInformant reports that in bid to maintain its competitive advantage while it preps Windows Longhorn for release over the next two years, Microsoft will not provide attendees at the Professional Developer Conference (PDC) in Los Angeles with the code for Aero, Longhorn's exciting and innovative graphical user interface. Instead, attendees will receive a special Longhorn build with the Aero bits removed, and Microsoft executives will only provide a special demonstration preview of Aero during Chairman Bill Gates' keynote address. I've now verified these plans with several sources at and close to Microsoft.