graeme_p - 8:29 am on Sep 13, 2013 (gmt 0)
Link buying: of course it works, as long as neither buyer nor seller gets caught. If you are not too obvious, you will not be caught. This is a bad thing for people like me who have free to use information sites (the economics of link buying work worse than they do for subscription or e-commerce sites), but I think its true.
Toolbar PR: sometimes so wildly inaccurate that I suspect its deliberately that way to throw off the link selling industry who rely on it.
Treatment of no-follow: I think it possible that no-follow links sometimes count. Reasons:
1) it is an obvious way of dealing with sites that indulge in page rank sculpting, no-following all external links etc.
2) Some no-follow links clearly have value: if spam links are cleaned up the remaining no-follow links are a useful indicator.
3) I had a page on my site that had a much higher toolbar PR than I could a. It had few internal links, and the external links I could find were all no-follow.