Don't say how came to this conclusion..
The Register: "In an effort to weed out the noise, Google constantly refines its weighting algorithm, which it says is a combination of a hundred different factors. In an attempt to thwart deliberate gaming by link farms and blog noise (exacerbated by lossy software gimmicks such as 'Trackbacks', which generate reams of content-free pages for Google's crawlers), Google has stepped back from its trademarked PageRank� method and instead, emphasized more traditional factors such as anchor text. "