Page-specific
Unique title tag
Unique meta description (Yahoo is the only one using meta keywords anymore)
One h1 tag (the text used in your h2-h4 tags is still very important, though)
Site-wide
Allow only quality outbound links (eg. rel="nofollow" on all user-generated links)
Block duplicate content from being indexed with robots.txt
Structure your CSS so the content can go first
Consistent navigation that allows bots to get to any page on your site within 2 or 3 clicks

http://www.pjhyett.com/posts/222-why-seo-is-important

Damn good tips

PJ Hyett : Why SEO is Important

code, web, design

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