I thought I'd post my brief views on Search Engine Optimisation. My aim is to help clear up some of the common misperceptions / bad ideas that non-technical people often have about it.
Focus on Google
Google has such a big market share that it's not worth spending much time trying to get results with other search engines. They have some extraordinarily talented engineers and a lot of vision, so I think its safe to assume that they'll be able to hold on to their market position for a fair while.
I suspect that MSN will begin to crush Google next year with billions of dollars of R&D and integration with Internet Explorer. This will bring new challenges for us and probably new anti-trust lawsuits for Microsoft. In the meantime, most SEO tricks that work for Google will probably work for MSN.
Incoming links are the key
Google's search rankings are mostly determined by their PageRank technology. This means that every site that links to your site is essentially "voting" for your site. The more people that link to you, the higher you'll appear in Google's search listings. If no one links to your site, it is likely that Google will never discover you.
Keep in mind also that everytime a user sees a link to you from another site, it builds your credibility. To a user a link is a personal recommendation, whereas to GoogleBot a link is a part of the mechanism for determing your page rank.
Don't waste much time on meta data
Meta data was important in the 1990s but modern search engines tend to ignore it - the actual content on the page and its relevance to the search terms is far more important. You'd be better off to spend time making sure your links are easy to follow for search engine bots, and cleaning your HTML up so it passes the W3C validation tests.
Search engine optimisation isn't a black art
http://google.com/webmasters/ documents exactly how to get good results from Google. Apparently reading has become so unfashionable that even SEO experts are unwilling to spend 30 minutes reviewing what Google's experts have to say.
The only sustainable strategy for building website traffic is content.
This will increase the amount of content Google can index. If people were prepared to write interesting content for their websites, more people would link to them and their PageRanks would subsequently increase. Common conversation as follows:
Marketing Manager: "My site isn't getting any traffic!"
Alex: "Really? What content do you have on it?"
Marketing Manager: "A few product descriptions and biographies of our board members."
Alex: "…"
All of the most successful sites either allow users to contribute content (http://photo.net, http://slashdot.org) or get content from external sources (http://google.com, http://news.google.com) or have huge teams of content producers (http://cnn.com, http://amazon.com) or sites that help users achieve something (http://orbitz.com, http://ebay.com).
The challenges involved in building these sorts of systems had all been overcome by the end of the 1990s. But for some reason, marketing people still think that their customers want to look at animated flash banners for 5 minutes and then read the CEO's biography.