Wikis are a cool tool for full collaboration. They would be great for a librarian/teacher collaboration on a student project that required research skills to accomplish their goal. The librarian and teacher could set a timeline of lessons that need to be taught and also a schedule for use of materials and technology. What would make a wiki appropriate for this is easy revisions, as we all know when you are teaching you are consinstly learning and discovering things that you thought would work or happen but don't always do. I would much rather meet at my house or complete school commitee tasks via a wiki verses in person meetings. I feel this way it would make everyone accountable to at least participate with a published comment.
A blog is two way as far as people making comments however unlike a wiki you don't want them messing with your stuff.
I plan on getting with a social studies teacher who is excited about collaborating with me ( YEHAA!) and see if we can do it with the use of a wiki to help us make a plan, stay on task as well as keeping us accountable.