What Google scholar has done is bring scholars and academics onto the web for their work in a way that Google alone did not. This has led to a greater use of social software and the rise of Web 2.0. For all its benefits, Web 2.0 has given us extreme info-glut which, in turn, will make Web 3.0 (and the semantic web) necessary.
I agree. Google Scholar (and Google) are very much Web 2.0 products. As I had elaborated in my previous entry, AJAX (which is Web 2.0-based), produced many remarkable programs such as Gmail and Google Earth.
Was this destiny? Not really. As Yihong Ding proposes, Web 2.0 did not choose Google; rather, it was Google that had decided to follow Web 2.0. If Yahoo had only known about the politics of the Web a little earlier, it might have precluded Google. (But that's for historians to analyze). Yahoo! realized the potential of Web 2.0 too late; it purchased Flickr without really understanding how to fit it into Yahoo!'s Web 1.0 universe.
Back to Dean's point. Google's strength might ultimately lead to its own demise. The PageRank algorithm might have a drawback similar to Yahoo!'s once dominant directory. Just as Yahoo! failed to catch up with the explosion of the Web, Google's PageRank will slowly lose its dominance due to the explosion caused by Web 2.0. With richer semantics, Google might not be willing to drastically alter its algorithm since it is Google's bread-and-butter. So that is why Google and Web 2.0 might be feeling the weight of the future fall too heavily on their shoulders.