I've been using a website as part of my classroom programme for several years but this year decided to use a wetpaint wiki (Cyberclassroom).
In the first term we learned about cyber-safety with an intensive unit called NetSmartz investigating the do's and don'ts of internet use. The reasoning behind this was because I wanted my students to have full use of the internet without too many restrictions. Good choices and peer / self monitoring were more important in my view than just blocking them from all and sundry. Making them responsible for their own internet use would equip them outside of the classroom and make my job much easier within it.
I chose wetpaint because of the treeview menu, meaning I could give each student their own folder and page without cluttering up the nav bar. Wetpaint also has some other good features like templates and widgets that are really easy to use.
With a class of 34 students it was a challenge but most were able to produce a quality page. We had to set some ground rules as well so that the children understood how we were to respect others efforts and also the process for drafting, editing and publishing.