wiki or not to wiki, is it a question?

Thursday a friend who is currently working on the phd program for ITS came up to me to talk about wikis. My son is actually a student in her World History 2 class, so they have been doing all the cool technology applications we are currently studying. He was excited, well, as excited as a 15-year old boy can ever be, about the pod casts they just completed. So, anyway, we were discussing how to use wikis. It seems to me I keep trying to plug these things in as final assessments. Like we discussed creating a wiki for a chapter, where, like we are doing in class, everyone is responsible for adding on to pieces. However, do I want this as a research on their own part and fill it in or as a end review? I have contemplated introducing wikis to them by having them create a survival guide to my classroom for next years class. That might be fun and interesting for me to read!