I had some breaking changes today when I tried to port some WPF code from the September CTP to the current (November) one. Some of the mini-languages in WPF are now gone. For those of you who haven’t been exposed much to WPF mini-languages are little non-xml pieces of short-hand that got stuffed into an attribute value - there is always a longer and more verbose equivalent. Some of the things that were removed for the Nov. CTP were the little mini-languages for specifying horizontal, vertical and linear gradients, radial gradients, the imbedded image mini-language and the transformation mini-language (more details are available here). Fortunately there is a conversion tool included in these samples to help ease the pain of migration. The thinking behind the removal of these is that nobody will create XAML by hand so adding these little special cases (that only serve to make code more succinct) don’t really serve any purpose. That’s all well-and-good going forward, but as things currently stand (without much designer support) there are a few instances where I’ve used the mini-language syntax. I think overall the disappearing mini-languages are a good thing. They make the platform simpler and more consistent, and I never found them terribly discoverable (which things could be represented using them and which could not).