setzer - 1:53 am on Jul 6, 2012 (gmt 0)
...that most of the web does not behave the way the SEO industry imagines it does... that the percentage of nofollowed links on the entire web is only a single-digit percentage, and "in fact it's a pretty small single-digit percentage".
Even so, it's unlikely a lot of old pages are using nofollow. I'd be interested in knowing the percentage of new pages in the past year or so that are nofollow. My guess is it's much higher than single-digit. I'm sure the majority of links are still do-follow but nofollow usage has been rising considerably from what I've seen.