Matt Cutts gives the definitive Google view on PR sculpting and the effect of nofollow – this will generate more questions than it answers, but there are the following takeaways: (a) you should still nofollow paid links; (b) the more nofollow links on a page, the less value the follow links have; (c) don’t nofollow any of your internal links; (d) basically avoid nofollow as an SEO process. It’s still a conceptual mess, but it’s taken some work off my to-do list…