I think this time I got it right.
http://xarg.net/tools/cvs/change-set-details?key=28373As for documentation, yes, you are right. Here is what you can do now:
When mapping a category tree you can define which widget you are going to use, radio, select, checkbox, multiselect. This in effect will set the parameters for multiple select or not.
Now you are able to control the look and feel of categories easier and better, hopefully making any custom "type" categories easily redundant.