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I was strongly considering building a Wiki for SEO topics for several months but never got around to it. ResearchBuzz reports about a Wiki for SEO at http://www.organicseo.org/.
The outline of the Wiki covers everything from the why of SEO to SEO terminology to URL rewriting to submitting your site to search engines to what not to do. It does not yet appear to be very filled out.
Hopefully the Wiki will grow quickly in Wiki fashion.
