But Google is already a hybrid model. The article even mentions AdSense, but completely ignores the Toolbar, Analytics, Ajax APIs, etc. etc. etc. Push or pull,

But Google is already a hybrid model. The article even mentions AdSense, but completely ignores the Toolbar, Analytics, Ajax APIs, etc. etc. etc. Push or pull, Google is absorbing URLs to crawl and index at a rate which no start up could match. Eventually, someone may dethrone Google, but it certainly won't be a tiny startup. Also, there is a significant portion of the web that could never be educated enough to ping some server. This approach is doomed to failure without a Crawler. That's not to say that there might not be interesting applications of their technology is news analysis or aggregation.