There was a recent update to the PageRank in Google.  There is speculation as to how those changes have affected websites.  So far, this is the only one I could find online.  I’m not sure how valid it is, but it’s a start.  And besides, do we ever REALLY know what Google’s doing?  And, taking it even one step further, is PageRank even worth anything anymore?  If you have any speculation as to the PageRank changing factors, let me know.

1. Internal links and external links on the same page may not be splitting the PageRank vote equally.
2. The location of the link affects PageRank.
3. Multiple links to the same url from the same page may not each get the same piece of the PR vote.
4. Run-of-site external links may reduce impact of PR.
5. Links between domains that Google sees as “related” may have their PR significantly damped down. Possibly the same goes for sites that link to subdomains.
6.  A major overhaul was made to the way content is parsed and separated into blocks (sidebar, main content, comments, footer) - and each block may have more or less value based on the relevance of the element on the page to the specific keyword.