Google, MSN and Yahoo! announced their support for rel="nofollow" attribute to hyperlinks. They will ignore links with this attribute to prevent comment spam. Movable Type and other blog software makers and service providers also announed their support. Movable Type released a plugin to modify all links in comments and trackbacks to include the rel="nofollow" attribute.
figby.com says: "Dishonest webmasters will use this attribute ... on all external links, to prevent precious PageRank from leaking out of their sites." and,