Rogers Cadenhead made some comments about Wikipedia marking all external links with rel="nofollow". I find it particularly unfortunate that Wikipedia typically only links to external sources that actually have subject matter quality - or at least are considered to have such quality by the Wikipedia author. Precisely a link monster like Wikipedia has improved the positioning of other pages through its links - which surely would have been particularly helpful for information websites about obscure topics. After all, who else would link to them?