Matt Cutts made big news last week with his blog post about "Text Links and Pagerank" where he asks advertisors to use the "rel=nofollow" tag when selling text links. The post itself as spawned a big list of comments that are worth reading. There’s another post by Tim at O’Reilly called "Search Engine Spam?" which has some great comments also worth reading, including comments by Matt as well. Including:
I’ve known about these O’Reilly links since at least 9/3/2003, and parts of perl.com, xml.com, etc. have not been trusted in terms of linkage for months and months. Remember that just because a site shows up for a "link:" command on Google does not mean that it passes PageRank, reputation, or anchortext.
I wonder how many people there are at Google just wacking sites with the ole "Block PageRank, Block Reputation, and block Anchortext" penalties. (anyone remember the old "BlockerPR" site?) You’d think some type of "block level analysis" could wipe out about 95% of ads (only counting links within content) (eh Google?)