[inertia]

Well,there's still a lot of argument about the effectiveness of nofollow tags so for the time being don't discount them! Also, the search engines still follow them but (apparently) they don't include them in your overall link profile. So they are still useful from an indexing point of view. There are also arguments about whether the link text still counts towards your "relevancy score".

The whole reason the nofollow tag was invented was for webmasters to a.) show the search engines that they don't have control over the content on the other end of the link and b.) to show that they haven't sold the link. So if the nofollow tag was invented purely for the linking out site then maybe the link still has some benefit to the site linked to?

All theories, but it should be enough to tell you not to think about the PR and just think about the traffic from those links.