We cross posted your reply and my edit. I think it was just a CSS caching issue, because it's not happening now.
One (microscopically minor) thing I've noticed is that in Firefox (2.0.something), the preview of an edited post does not italicise the quotes in the post. IE italihandles it properly. It's one of those things that's so small I would never have noticed or mentioned it if it wasn't a thread about fonts. It might be that it's always done it, I don't know if I've ever previewed an edit before now. Or it might be more of that caching stuff and will sort itself out once my browser is back in sync with the site.
In either case, I'm just pointing it out as an oddity, not a complaint. Wholeheartedly enjoying almost everything about the new setup.