For the first time ever the help system will be user customizable; users can add their own notes to the pages for future reference.

Hope they allow you to share these annotations through some kind of community, but sounds cool.

[source: ars technica]

Rod PaddockRod Paddock has been posting a great series on Avalon.

So download the Avalon CTP and start writing some code.

Chris Sells starts developing Longhorn's most importand application by addressing issues with the current version.

Inspired by this initiative I started porting Minesweeper to .Net (Whidbey), with the next step, a Longhorn version, when I get a capable machine.

Everything you always wanted to know about developing for Longhorn with the PDC build, is now compiled in the longhorn FAQ on MSDN.

The XAML IntelliSence Patch for PDC Visual Studio .NET "Whidbey" shows Microsoft is commited to getting developers ready for Longhorn.