netmeg posted in another thread that she gives out dofollow links to sites that she thinks would be useful to the visitors to HER page.
Yep, same here. A link is a way to direct users to a more comprehensive (or, in some cases, an official) source of information on a topic. If you're writing an article about your favorite childhood comic books and you mention Little Dot, it would make sense to link to a detailed Web page about Little Dot (as opposed to writing a history of the Little Dot comic books yourself).
Evidently in Google's view, a dofollow link from some obscure personal blog should count for more than a nofollow link from the NY Times or Harvard University.
For that matter, a purchased link from a second-rate directory counts for more than a nofollowed NY Times or Harvard University link (at least until the link seller or buyer gets caught).