There is yet another Web2.0 application to help us with organizing and GTDing, Wridea (from the webpage):

Wridea has easy to use interface that lets you create, edit and delete your ideas, pages and categories easily.

Getting things done. There are five core principles in GTD. Collect, create ideas in wridea, Process, move them to another categories and pages or delete them, Organize, create pages or categories for next actions, projects, waiting for and someday/maybe, Review, browse your ideas easily and finally Do, this is your thing.

http://www.wridea.com/

I haven't tried it yet, but I will since it looks interesting.