Its been a while since XUL Explorer has been updated. However, I have been using it more than ever and I have been keeping a list of things that I’d like to see added. The good news is XUL Explorer is now hosted in Mozilla’s SVN repository. More good news is we created a wiki page to help track and guide development. Even more good news is that Cesar Oliviera has joined Developer Relations as a summer intern to help work on developer tools.
Feel free to use the wiki Talk page to discuss XUL Explorer features and roadmap.