Gives you the choice between the simple "picker" which pops up an extended palette, and the "selector" which provides an advanced Photoshop-style color selector for greater control over the color being chosen.
If you want to stick to the old picker, no changes are necessary. To switch to the new selector is easy, just update your config.xml file, and replace "picker" with "selector".
For more information read the section on the Color Palette.
This version also includes a new "base" parameter which can be used to define the base directory under which the other folders should be found.