The wiki my students have is a closed one so that my learners don't feel uncomfortable doing their writing assignments. It is linked to a talkgroup on Voxopop where they record their speaking tasks. Introduction to IELTS speaking section is an embedded Prezi presentation; the explanation of how to record on Voxopop is a screencast done with Screenr, the videos that I would like my students to watch and the tutorials about how to do the writing tasks are in a MentorMob playlist also embedded into the wiki. There are also some screenshots done with ScreenHunter to explain what the buttons on MentorMob are.
When it comes to choosing which tool to use, I suppose, each one of us chooses the one that is more convenient for them. For example, I always use pbworks if I have to set up a wiki. I am not really sure why I prefer this site, because others do more or less the same. It may be a question of habit-formation or preference. The same is true for screencast tools: I always go with Screenr, but I know that other tools are just as good. This is the presentation of the tools and the wiki I gave yesterday. However, I would like to ask a question: Do you always use the same tools? Why/Why not?