Very interesting... I'm using the w.blogger tool to do my editing. It seems very nice to use instead of the web form. Though I think in general, since it's not actually showing me wyswyg, it's just about the same. Though the preview is quick and easy, it's not the same.... Except for the ability to edit old posts, i think that an Email interface would probably be the best.
If you're reading this, go to www.russellbeattie.com. That's where my site is.