Speaking as a former member of the WPF graphics team … MS is not really great at supporting / developing the teams that make their UI frameworks. Vicious internal competition produces a new internal tribe that self-promotes a new framework every few years. These things slosh around between devdiv and windows, with the managers stealing resources from each other and undermining each other’s efforts. I watched WPF get gutted between 2008 and 2011 (the three years I was there) because Silverlight was able to ship (low quality crap) more often. WPF has been on skeleton crew life support for years. It’s really ugly under the surface, a brittle monolith full of unfixable bugs. Some of the code clearly written as a joke. Silverlight is worse, the new windows xaml is just as bad. The old IE6 team (yes, it’s them) really lacks the discipline to make a solid product, so it’s just a huge pile of unstable shortcuts stacked on top of each other. I wouldn’t waste time investing heavily in it.
The new company reorg _might_ result in more cooperation than coopetition, and produce a stable and useful UI framework. Wait for that.
Until then, stick with things that people can easily dovetail in with their code – anyone worth their salt can write the UI glue to bind to data brought in by event handlers.