Ok first things first, credit goes to DC member Veign - I read about it first on his blog, Unhandled Perception
Anderson (wordzilla) and I checked out a ton of Help Desk and FAQ tools, both open source and commercial, before going with this kbp.
There are some serious Help Desk tools that support tickets and assigning tasks to support personel, etc. If you need that kind of stuff then kbp is definitely not for you. Although I call it a help desk, it's really a FAQ system but with some functionality for users to leave comments and submit contact forms, etc.
Like many open source projects, it is a bit uneven. It has almost no documentation and there are small things missing.
I did a solid days work customizing and writing php code to improve the contact submission forms and do other stuff like add translation buttons, and tweak the look and feel.
However I just love the clean feel of it, and the administration panel is suprisingly rich. It is extremely easy to work with and works well and looks good right out of the box even without any modifications.
Normal users cannot add their own FAQ entries BUT it does have a full role management system so you can add editors who are allowed to add entries, etc. It would be easy to give editing permission to a whole bunch of people.