According to ComScore, Google has around 66% of the market share. Microsoft is at 16%, and Yahoo is close behind at 13%. These are the top 3 companies, and even if they combined forces, they wouldn't be a match for Google. Speaking of underdogs, Ask.com is around 3%, and AOL is just a hair over 1.5% of the search market.
These percentages roughly translate into advertising profit. As a company's percentages drop, so does their revenue, making it harder to increase their search volume. The search market was far more diverse a decade ago, but, are we worse off? Perhaps that's a question to Google.
What do you think?