Here’s a nice article on SEO, which lists the “durable” seo elements to focus on for your website:

http://searchenginewatch.com/article/2111842/8-Durable-SEO-Elements

An interesting revelation from Google CEO Eric Schmidt – google changes their search algorithm a little bit each day.  EACH DAY!  So jumping onto the latest hot SEO tip may backfire.

I’d summarize this article as follows – make your site user friendly and provide great content.  That’s it.  Serve your constituency well, and the search engines will reward you.