Sort of what Mixture says.
Google likes fresh content, and will rank you higher dependent upon how much content you refresh regularly.
It also likes backlinks (people linking to your site) but these should be relevant and not paid.
However, you're onto a loser if your site itself isn't well designed with respect to HTML and search. You're also onto a loser if you're trying to chase popular search terms, because the big boys in those arenas will have chucked money at it.
(Can you tell my business partner is totally into his
SEO?)