Already used in…
At the moment (since it is not published yet) library is succesfully used in two of my own projects.
One of them is HK Uploader for Images hosting – it allows to quickly upload any of Your images to online hosting and share the links through web.
Other one is GUI Machine – a brand new application for rich and interactive prototypes creation.
Most of the interface features that are going to be introduced in GUI Machine or HK Uploader will get into WebLookAndFeel library as an extended components, UIs improvements or side-features. So it will grow much bigger and will get a rich set of styled components in it.