The fight between search engine domination was started by Google. First Google launched Google Toolbar for Firefox. Then they started paying publishers referral fee for downloading Firefox. In return Firefox make money for you searching Google from the browser (search bar on the top left). Then Google started paying Dell 1 billion dollar for installing Google toolbar on Dell machines. In Safari Google is almost impossible to change from default search engine. Google then took 5% ownership on AOL, so that AOL would use Google Search.
Microsoft in return put a search bar on IE 7+ with MSN search as default. Alexa then dropped Google from there search. Alexa’s parent company Amazon, then dropped Google from A9. Its also rumored Ebay is in talks with Yahoo.
All this followed by Marisa Mayer from Google, screaming anti-trust. More fun is yet to come.