These are all really great and creative online services that could be used both in the classroom and when working with peers. More specifically, I would like to use Tagxedo or Word Clouds as a brainstorming tool in our writing.
Bubble.us and Gliffy could be used when showing relationships between different stories or when teaching word relationships (i.e. adjectives, nouns, verbs, etc.).
I would like to spend more time with some of these programs to see if they will interface with Keynote or other software we currently have at school. I'm also curious if they are interactive at all.