I'm usually a minimal, basic colours kind of guy and never thought I'd change from StreamedMP but Titan is absolutely gorgeous.
Eagerly awaiting an editor so I can clean up the icons and remove those I don't use though. As most have said, an external editor is fine due to how little the options are changed once it's been set up initially.
Plus, nothing is more confusing to guests/spouses/girlfriends than hitting the 'up' or 'right' arrow on the remote too many times and having an options-laden menu appear.
Instead of building a Titan specific menu editor it would be much better use for the development resources to start to work with the MP core functionality that would allow other skins as well to use the centraliced home screen editor. No point in doing double work.