when I think about wiki, I usually think about wikipedia - it is one large knowledge-base. ok, I don't intend course wikis to become large, but I would like them to be connected in some wiki fashion (categories?) - to be actually one wiki. Then You could use wiki-linking among them .
waka branches wackowiki and winiwiki have nice filesystem style categorization mechanism. Twiki also has sth similar. Don't know about e-wiki?
one more argument, is that wikis usually are not temporaly, they grab some idea and then goes on developing it (like primarily Universe explosion ).
well, but all this stuff wouldn't do good for wiki grading. I just posted some proposals there so now I am confused :.