According to Alexa, Yahoo! is the #4 site on the internet, and Windows Live is the #7 site. So the millions of people who have Yahoo! and Windows Live for their homepages (and this is very common--remember that IE is still the dominant browser, and it defaults to Windows Live) are aware of those search engines.

The reason Google is the search leader is not because nontechnical people don't know of the alternatives. It's the leader because it's synonymous with search and people think it's the best.

Google is often set as the default search engine for IE in preinstalled OEM configurations (and frequently these days Chrome is the default browser). For antitrust reasons Microsoft can do nothing about this.

Chrome asks you to choose a default search engine when you install it. What more can they do?

Heck, I'm not sure most people know what a search engine is. Wasn't "Google" one of the most-often heard answers to the question, "What is a browser?"