Here is a useful article from IRRODL titled “Educational Wikis: features and selection criteria”. With over 200 wiki engines to choose from, any guidance is certainly good to have when choosing a wiki technology. Here, the authors have identified basic selection criteria based on a wiki’s features … but I guess it’s up to us to actually perform the side-by-side comparisons. Is there a decent comparison out there?

See the full article here:
http://www.irrodl.org/content/v5.1/technote_xxvii.html