I was finally able to find time to put true WYSIWYG HTML editing into JoeBlogger.
Here is a current screenshot:
Notice that there is no save button. Just start a new entry and hit Upload.
It FTPs everything that has changed to your site on a background thread. If you don't
hit upload, it will automatically save your unpublished entry. I really like
the UI model with no explicit "save" functionality.
I stole the HTML editing control code (which is really a wrapper around IE's rendering engine: Trident) from ChrisAn's BlogX. He stole it from Nikhil Kothari who wrote it originally ASP.NET WebMatrix project. The HTML -> XHTML conversion code was written by Andrew Lin.
Note that JoeBlogger is a very different project than BlogX. BlogX is a client/server solution that has the canonical data store on the server. It requires a ASP.Net server to run the server side part (Actually, you could probably write a different server that expose the same API, but you get the idea). JoeBlogger is a client side only solution that doesn't have any server side code at all. All of the pages are generated on the client and uploaded to the server. As long as you have FTP access to your web server (and almost everyone does) you are set.
If you are interested in getting a look at the JoeBlogger source, let me know and I can give you an early drop of the source. I'll probably add some more features (and a decent setup) and then release it.