In our continued coverage of the a WebmasterWorld thread started by senior member CainIV, we learn two more things. These two items are likely obvious to most, but have been confirmed (at least to CainIV) that they are true based on his experiments.
- Changes to navigation links can have a serious impact on a site's ranking in Google. CainIV said, "there are certainly nav and footer link thresholds that cause a website - even a website into the top 5 - to spin out and down to pages 5 and 6 in ranking."
- Navigation links are treated differently then links within the content. CainIV said, "Google appears to handle thresholds from links within content different than those within nav or footer sections - this is to say, that content links have a fuzzier 'trust' logic about them, and I could more links to content, faster and more focused on the primary keyword pointed at the root url without the same threshold being crossed."
Like I said and like CainIV said in the thread, this is likely all assumed already but can't hurt to validate it.
Forum discussion at WebmasterWorld.