It is a WPF app and it is freaking sweet. The reason why it took so long was probably because the performance sucks...and you know what it is probably Microsoft's fault...this is sad. This is probably why Microsoft doesn't use it.
Switcher suffers the same performance issues, which the author blames on Windows.
I don't know, I didn't have any performance issues. All they need to do is code intelligently. Use StaticResources instead of DynamicResources...etc.
We used to have performance issues until 3.5 was released. Cleared a lot of them up, but of course WPF is providing a HIGH quality GUI with a lot of storyboards, yes it's likely any program will be slower.
Not to mention it kind of looks like they were animating things with BitmapEffects..that's just asking for a slideshow.