Unfortunately there are lots of people who do use shady tactics to promote their sites - and simple grassroots whitehat SEO practises are really all one should

Unfortunately there are lots of people who do use shady tactics to promote their sites - and simple grassroots whitehat SEO practises are really all one should focus on. Google and Yahoo can, and do change the rules of the game all the time by changing their algorithm, so just make sure you have your bases covered with the things that you cant get pinged for.