I have not seen this before, but I did like what I saw in the links that you provided.  Really seems like a nice use of ajax for an editor.  I did some googling and didn't find any much about using the componentart editor with DNN.  I did see a few things on using componentart products with DNN. I'm interested in starting, at least with the editor.

On second look, it's missing image/document upload capability -- is that one of the things to look at adding into it?  Also table manipulation is a little missing.  On the plus side, numbering and bulleting appears to be a little more sophisticated than current FCKeditor...and I wouldn't have to explain what FCK to everyone...it's not what they think.

Quite cool looking and clearly slick, but I still find image management to be the biggest failing with all of these editors. Images are such a significant part of content publishing, yet year after year it is an aspect that is completely ignored by the developers. They all process text perfectly well, and really, I'm completely unconvinced that cross browser consistency of the code-behind and this or that standards compliance is of any relevance to content creators. I certainly have yet to meet anyone who would care.

If they added image processing to their strategic plan then I'll definitely cheer for it - much like I cheered for FCK back in the days too.

I may however have missed further benefits of the product?

Rob