Wiki weakness?

Wikis seem to have become my Web 2.0 "experimental flavour" of the moment.

I have FIVE different wikis, all hosted at http://www.pbwiki.com. I have one for the Masters class I was teaching earlier this year, a service learning class that stretches over two semesters, a wiki for my trainee teachers' practicum "files", an administrative wiki for my department, and a personal wiki that I use for training and recording research ideas.

I chose PBwiki for two main reasons: it was very easy to set up and it has a WYSIWYG editing tool that I like.