I am a computer consultant. Right now I am using XOOPS and testing TikiWiki. What I like more on XOOPS is, that it is object orientated. I think the sourcecode will be more easy to administer. What i like ton Tiki is, that it is heavy. You get everything you might need.
Documentation is surely too few.
Best in Tiki is integration. Writing news with Wikinames and than have them explained in a Wiki - this is cool!