If you're from further down the developer end of the designer-developer spectrum chances are you've been avoiding creating your own images, and on the look-out for some good XAML icons and vector images to include in your application, since bitmap images often look blurry. While we included some XAML image resources in the past there are plenty of other good resources out on the web if you know what to look for. Although no graphic designers are sitting at home churning out XAML code per-se, there are plenty of ways to convert the vector content they produce (like SVG files or Adobe Illustrator .ai files) to XAML. Here we've included two sites to get you started, and approaches for converting other vector formats into XAML.
OpenClipArt.org is a repository of "open source" vector art stored in SVG format. SVG is an XML-based vector format (and thus you could transform it yourself to XAML if you wished), however there is already an excellent tool from Andrej Benedik from WPF-graphics.com for doing this. You can also use the free and open-source InkScape editor to edit SVG files. Many of the images are licensed in the public domain, meaning you can use them for pretty much any purpose. Shown below is a mac-like SVG image of a new computer by "big red smile" (possibly not their real name) beside the converted XAML version displayed in Kaxaml.
vecteezy.com is a "free vector art of the day" type site, with nice vector backgrounds and images released under a variety of terms (so make sure you check the license on the image). Most of the files here are Adobe Illustrator .ai files. If you have Illustrator installed you can use Mike Swanson's exporter, however if you're a developer that is less likely. Expression Design (now included in MSDN universal) can import Illustrator .ai files. For some reason it can't open them directly (if you select File->Open and then try to browse for a .ai file it won't let you) so you need to create a new blank file, and then select File->Import and browse for the .au file. Once in Expression Design you select File->Export and select Xaml as the type from the dropdown list. You can then choose how the xaml is formed when you export it.