I love the concept of wikis, the subject of this week's (admission: I'm a week late, so it was last week's) assignment. After reading The Wisdom of Crowds a few years ago as well as some data on the error rate in the Encyclopedia Britannica vs. Wikipedia (surprisingly favorable to Wikipedia, as I recall), I began to comprehend the power of wikis.
Of course, Wikipedia has quality control, something that cannot be assumed for your everyday wiki. Still, the fact that people might add to each others' knowledge in an area of mutual interest can be truly helpful. One needs to sift the information as one always does, but if someone says something intelligent, well, it's intelligent, and if there's a reference to an article in a journal that you know is respectable, you may have saved yourself tons of time finding just what you need to fill in an information or idea gap that you've got. So I'm all for wikis, and would like to see more of them.
In Jewish education we could use wikis on, for example, teaching t'fillah, how to initiate Israeli teachers into America school culture, how to extend the range of day school education to incorporate experiential education, project-based learning in day schools, etc.