Recently Google’s Matt Cutts “sort of” announced an algorithm change designed to address overly optimized or “SEO’ed” sites. No one is sure when the algorithm change will take place or if it already has. Recent speculation points to summer of 2012. In the words of Matt Kutts, “We are trying to level the playing field a bit. All those people doing, for lack of a better word, over optimization or overly SEO – versus those making great content and great site.”
No one really knows what “overly optimized” is vs “optimized just right”.   I always thought that Google has already addressed most of the “on page” excess optimization factors like keywords being repeated excessively, but I know that at least one site that I am competing against seems to repeat keywords beyond the absurdity level and they are still ranking on the first page on some their targeted keywords. Maybe the algorithm change addresses that, but in reality the “amateur SEO guy”, doing some work on his own “mom and pop” site is the most likely person to do the spammy stuff.  It is doubtful that Google wants to punish the “mom and pop” sites.  Most professional SEO experts are going to avoid some the obvious stuff like the plague.
So maybe Google in its never ending quest to destroy the SEO [black hat] industry is going to focus on stuff that only the highly experienced and knowledgeable experts would use.  Certainly link building should be a primary suspect.
The best strategy to combat over optimization penalties is focus on creating unique, engaging and well written content on your site.   Those of us who primarily focus on content generation over “SEO tricks” should feel safe and perhaps somewhat vindicated by this news.