Bad news for SEO companies - google have recently announced that they are changing their search algorithm to make it fairer for websites without SEO. Matt Cutts, speaking at the SXSW 2012 conference said that they were working on adding a penalty for sites with overly optimised and  SEO heavy pages and will be implimented in the next few weeks. In the announcement he said:

the idea is basically to try and level the playing ground a little bit. So all those people who have sort of been doing, for lack of a better word, “over optimization” or “overly” doing their SEO, compared to the people who are just making great content and trying to make a fantastic site, we want to sort of make that playing field a little bit more level
(source: searchengineland.com)

There has always been a penalty for 'keyword stuffing' - ie adding too much repetition of keywords in a page. Now what this means is that if you have spent too much time optimising your website, adding SEO targeted keyword in your header tags and content, SEO optimised internal links and SEO rich metatags, you might fall foul of the SEO penalty even if you have relatively good content. The level at which a site is deemed to be 'over-optimised' has not been divulged and it will take a while for SEO software to update their page optimisation analysis tools to incorporate these latest changes, so you will not know whether you are affected by the penalty until the new algorithm is rolled out.

All we know is that there is another google ranking storm coming. So batten the hatches, lower the sails and prepare to de-optimise your websites if they start sinking.