Fortunately, I - and many of my classmates - are familiar with wikis. Not just because we use Wikipedia at times, but because we had to set one up for one of our previous classes. I like the idea of complete and total collaboration. No one person can really bully his/her way into becoming the ringleader. It's about checks and balances, and no opinion or critique is more valuable than any other opinion or critique. As far as sharing and adding reviews and/or editorials goes, wikis are very cool to use. The Blogging Libraries Wiki and The Book Lovers Wiki are great examples of this sharing of ideas. However, I do have some reservations about the most famous wiki of all, Wikipedia. I know my credibility is somewhat shot because I mentioned in the first sentence that I definitely use Wikipedia at times, but how can that information be trusted? When people go to that website to look something up, more often than not I'm guessing they're assuming that the information is reliable. That's a big, big assumption, and if you are using it as an absolute factual resource, then you are taking your chances.
I don't mean to be a downer, because I think wikis are an excellent learning tool. I think it goes something like this:
Sharing ideas/opinions/reviews on wikis = Really useful and helpful
Sharing 'facts' on wikis = It can be reliable, but it can also be difficult to separate actual fact from information that someone perceives as fact but actually is a little off