Not wanting to be left completely behind, Yahoo will soon launch their own real time search engine too. But unlike Microsoft and Google, they won’t be partnering with Twitter and Facebook directly for the data (perhaps memories of their ill-fated blog search engine from 2005 linger). They’ll work with one of the existing real time search engines – that partner is OneRiot.
http://www.techcrunch.com/2009/10/27/yahoo-to-launch-real-time-search-too/
The main reason people like the concept of forming an SEO Monopoly is leverage. Traditional SEO is like putting all of your eggs into one basket. An SEO Monopoly is equivalent to owning multiple baskets. The odds of a the searcher finding out about your company or service are much greater if you are running an SEO Monopoly.