In addition to releasing the .NET Framework 3.5 SP1 last week, which included a number of improvements to WPF, the WPF Codeplex site went public. This site is the home for the WPF Toolkit and WPF Futures.
From the site:
"The WPF Toolkit is a collection of WPF features and components that are being made available outside of the normal .NET Framework ship cycle. The WPF Toolkit not only allows users to get new functionality more quickly, but allows an efficient means for giving feedback to the product team. Many of the features will be released with full source code as well. The Toolkit Roadmap outlines some of the upcoming features we have planned."
"WPF Futures includes sample controls and features, many of which are being considered for the Toolkit. Check out the Futures Roadmap to see some of the features we have planned."
The first CTP of the WPF Toolkit includes the new WPF Datagrid. Future releases will include a DatePicker/Calendar and more. Jaime Rodriguez already has 3 posts on the Datagrid:
dabbling around the new WPF datagrid (part 1)
datagrid (part 2) -- Show me some code
Datagrid (part3): styling
While I am at it, Jaime has a nice little "cheat-sheet to some of the WPF 3.5 SP1 features" at http://blogs.msdn.com/jaimer/archive/2008/08/15/cheat-sheet-to-some-of-the-wpf-3-5-sp1-features.aspx.