There is some great stuff hidden in Time Sneath’s post announcing the WPF aspects of the .net 3.5 SPI release:

It's been a long time in coming, but we're finally adding the much-requested DataGrid control to WPF. This will ship out-of-band at first, just after we release 3.5 SP1…

...Another oft-requested control is the Office Ribbon, and I'm sure you'll be pleased to know that we're also shipping an implementation of that control, also out-of-band, before the end of the year. The ribbon will be fully implemented in WPF,

So there you have it, there is a DataGrid and a Ribbon control coming to WPF! This is really cool. Something else that is really great is it appears that the WPF team is starting to adopt the “out of band” release model that other developer tools such as Asp.net MVC are using. I think this is a huge step forward in terms of integrating customer feedback into their products.