A somewhat hidden myth is the myth that content about the content helps in search rankings.

I find that not only does it do that - it also brings a useful service to the visitors, telling them about what it is, they are looking at.

When they go to a category listing, it doesn't hurt to tell them what they can expect to find in that category. And if a searched word is both on the category page, in the article teaser AND feature heavily in the linked article, it really shows Google that it is an important word.

It is also a great way to get words onto the site - in a relevant context - without having to rely on articles containing it. Sometimes the best search results are not the ones that contain the word, but the ones that contain other words that define the first one.

Conclusion #3

Google - and most other search engines worth mentioning - are based on two things: Content and Relevance.

Lots of content = Frequent crawls by search engines
High relevance to searched phrases = high position in the search results

The conclusion is simple: Produce content of high quality with lots of relevance for the words for which you want your site to be found in searches and the search result ranking will make its way to the top by itself.