This is pretty cool.
I am editing this post on the- sorry just tesing and trying to understand the concept
If I try to edit this post by clicking "Edit Post" in the WP admin bar, I get redirected to the home page. If I click the small "Edit" link in the post meta section, it works. The WP admin bar link should be fixed or removed.
I like the idea of meshing Etherpad with WP.
Too bad there's not another person here with me to test the collaborative piece.