Can somebody point me to a resource describing comprehesively what new Skinning features are available in DNN5??

In particular, I checked the Extropy skin that ships with DNN5. It has a stylesheet folder, which further has layouts, menus, palettes, textsizes, and widgets sub-folders.

In the palettes, there are multiple color-named folders that can completely change the look-and-feel of a site. However, I could not find a way to switch between palettes. Can somebody tell me how I do this??

I did not really had a look at it. And I am having it (a look) now.