Most widely used WPF client application development frameworks

I done some research on WPF client application development frameworks and eventually found out three most used framework and one yet to be mature framework. I thought its worth sharing the research result

1. Prism

http://compositewpf.codeplex.com/

Impression : Most advance framework

2. Caliburn

http://caliburn.codeplex.com/

Impression : Advanced  framework

3. Cinch

http://cinch.codeplex.com/

Impression : Solved particular set of problems and can be used along with other framework

4. WPF Application Framework (WAF)

http://waf.codeplex.com/

Impression: Primitive and useful framework to develop MVVM pattern based application

All the application framework used MVVM pattern to develop the applications, I am sure this frameworks are worth learning and will definitely help us in career.