I have an established site (since 1999) that ranks in Google's top 20 for most of my key terms in a competitive market. A large number of high quality external links PR 5 - PR 7 have been sine June 2004. Since June there has been absolutly no change to the postion of my site in the serps. I belive that these new links are still waiting to be taken into account by Google for whatever reason. It seems the only logical conclusion that I can make. I would be interested to hear whether anyone has had a similar experience.