Rob Toledo, Head of Outreach at the Moz Blog wrote an excellent article recently about the value of nofollow links. And the value, according to Mr. Toledo, is not in the building of a balanced linking profile as one would assume.
According to Mr. Toledo, “Eliminating a site from a prospect list just because it nofollows links is focusing far too much on the minimal value one link provides. I would argue that in any online marketing campaign, nofollows not only have a place but should be sought after as part of the overall strategy.
“To be clear, I’m not talking about trying to maintain some healthy ratio of link types in a site’s profile; I’m talking about actively pursuing nofollows with the intention of gaining the benefits they bring almost entirely unrelated to organic search.”
For the entire article, read this.