As someone who has been using Gobby for real-time collaborative coding recently, Etherpad is appealing because it is amazingly temping to link Etherpad with SVN. Imagine being able to have each author's changes automatically checked in to a repository on save.<p>One of the most limiting factors of Gobby is that access control is virtually non-existent, and it has no integration with any sort of version control. Hooks and scripts are required to hack up source control systems.<p>It seems like a startup would do quite well to create a service combining Etherpad and SVN (or another flavor of version control).<p>All that said, Gobby is a pretty fun solution for private collaborative editing. Watching colleagues fix your mistakes in real time (and doing it for them) never gets old.<p>[1] <a href="http://gobby.0x539.de/trac/" rel="nofollow">http://gobby.0x539.de/trac/</a>