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My pleasure. While I'm still thinking about backlink profiles, there's a post by John Doherty about analyzing your backlink profile vs. competitors based upon Domain Authority. I think this is a more worthwhile way to analyze your own backlink profile for spam. I won't speculate if Google is doing anything similar. You can find the article here: http://www.johnfdoherty.com/three-phenomenal-excel-spreadsheets-for-link-analysis/ Also read this follow up post about what a bad backlink DA profile will look like: http://www.johnfdoherty.com/paid-links-backlink-profile-visualized/