In these days of holidays (before starting for my real holiday at the sea) I've spent some of my free time to improve my knowledge about Windows Presentation Foundation. I've to admit that WPF has never attracted me too much (my first impression was that it's too designer-oriented) but this is the future of windows client development so... I'm forced to well undertand it for the near future.
From my first WPF view (during the alpha versions of VS 2008) I've to admit that the last Visual Studio 2008 Beta 2 has lots of improvement around WPF development. Cider (the new WPF application designer) is well integrated into the VS 2008 IDE, the XAML editor has a nice intellisense that works, the designer surface is nice (the snap lines and margin guides helps a lot) and the zoom control is really helpful to focus your attention on the UI parts you've to work with.
I've appreciated a lot the "double view" between the XAML editor and the UI designer: you can edit your customizations directly into the XAML editor and the designer will reflect the modifications (and viceversa).
However, there are not only marvellous things... 
I don't like for example that you can't add nested elements directly via the designer. In order to create nested elements, you've to design the control and then manually edit the XAML code in order to insert it in the correct block. Not always so quick and easy...
The same for control alignment or for the "fill to content" feature: you've to manually edit the XAML. Why?
Why there's no support for templates and styles when designing a control?
My conclusion after these days of little "WPF Learning" is that Cider is improved and actually is usable for production, but in order to create powerful and attractive WPF applications, you are forced to use in conjunction with Visual Studio 2008 a tool like Expression Blend.
Maybe because I'm not a graphic lover or maybe because I've never too much understood Flash, but I'm really not in confidence with a tool like Expression Blend. 
I think it's too much designer-oriented and the idea to have two tools in order to create a Wndows application really doesn't attract me too much.
Unfortunately, the roles separation between a developer and a designer is not always possible (although recommended), so I think that we (developers) will have to become familiar with these two tools for sure...
Sigh... 