And the winner is...

... the w.bloggar plugin for SharpReader

That was the only one that gave me a clean minimal fuss ability to post non-ASCII characters.

The BlogThis button on the Google Toolbar using IE failed miserably.

The BlogThis extension for Firefox wasn't much better. I had to separately copy/paste the non-ASCII text into the blog posting window. And what went out in email was... wrong ... possibly missing the proper encoding tag.