I'm using WordPress SEO 1.1.9 with WordPress 3.3.2. My sitemaps (http://unlikelyexplanations.com/sitemap_index.xml and the sitemaps that it points to) look fine when I view them in Safari or Chrome, but when I view them in Firefox (13.0 on a Mac), I get this:
Error loading stylesheet: An unknown error has occurred (80004004)
I'm guessing that robots ignore stylesheets, so this probably won't cause any real problems, but I thought I'd mention it because it made me think my sitemaps were broken earlier today.
P.S. I saw the other thread regarding sitemaps and stylesheets, but I think this is an entirely different issue, since the error codes are different and there are no redirects involved in my requests.