Puzzled over Flash MX WYSIWYG editor

Dave points to a Flash MX WYSIWYG text editor at Illogicz.com. I’d actually seen it before, but the lack of a Submit button was puzzling and raised a bunch of questions:

If I wanted to integrate this editor into a browser-based application, how would I get the text back out? Does it do an HTTP POST?

Do I have to rely on JavaScript as well as Flash MX?

What browsers and platforms is it compatible with? What ones is it not compatible with?

How would a server know whether to embed the editor as opposed to a plain-Jane textarea? Is there a way for the server to detect that the required Flash MX client-side stuff is installed?

A guide for busy developers would be helpful…