Natural listings are an ever-decreasing slice of the pie and I can't see that slowing down. That's not new.
SEO and SEM will become the next internet dinosours if google fails to adequately monetise it's natural listings product.
"Buy Google stock" jokes Gates. He'd love it if you did. What he actually means is "Buy Google stock and then insist on getting a decent commercial return from your investment".
Bill Gates doesn't like to share his pie.
Google are gambling that it can monetise natural listings by biasing them towards informational resources and getting money from the publishers through AdSense, combined with revenue from e-mails through gmail.
Bill Gates is gambling that they will fail. And he seems pretty confident to me.