thanks both, both very interesting links and articles. 
How about something I can put in quotation marks with a maven's name behind, thinking like "I think SEO is great!" Avanish Kaushik - google.

Hi all,

I'm looking to put together a presentation on SEO and I'm wondering if anyone knows any good quotes that relate to the importance of having content on your site that people want to use and share. I'm looking for something like this:

“Today’s marketing success comes from self-publishing Web content that people want to share. It’s not about gimmicks. It’s not about paying an agency to interrupt others.”

• David Meerman Scott “The New Rules of Marketing and PR”

but ideally something that illustrates in terms of numbers how much more traffic and seo benefits a site can expect from having good guides, pdfs and news stories that people want to share.

Thanks so much for any helo you can offer.

thanks,

David