I like elegant HTML. I love what CSS does for documents in allowing us to to keep it as such. WYSIWYG editors seem to be staying in the dark ages unfortunately, generating <font> tags and throwing all kinds of tag soup. It's really time for us to move up. I understand that users are used to the way that these editors work--the terrible MS Word way--but it's time to train them in the use of a standards based editor. Where the only styles that are controlled by the editor are the ones that add meaning to the text, rather than styling the text to fit the situation.
I'm not saying that users shouldn't have control of the styles of their writing, but it should be controlled in a standards-based way. Let them edit the stylesheet of the document.
HTML is actually pretty well suited for writing if we just use the standards correctly.
I've seen the WYSIWYM Editor. It's interesting as a proof of concept but a better implementation is necessary if there's going to be any kind of broad adoption.
There have been some text formating languages that are pretty cool. I like markdown, but it's not quite usable enough to drop on users and expect them to figure out. Maybe some kind of hybrid markdown/wysiwyg editor would work. I had an idea for a HTML Editor a while back that would allow you to see and drag around the tags in the source while in preview mode. I called it X-Ray Editor, because you could see into the HTML without having to see only HTML. I'd still like to see the project come to fruition, but it seems like a daunting task as a side project.