I'm not sure whether AboutUs.org is somehow hiding the rel="nofollow", but I know that they give complete pages DoFollow links only if you ask them.
Shoot AboutUs.org an email at dofollow@aboutus.org and see whether the pages have been cleared. If they have, just wait for OSE to catch up.
I completely agree with Nakul's point about not worrying about appearing in Online Site Explorer. Just look at Google first.