When you mention the Big 3 in our industry, you don't think Ford, GM and Chrysler (unless you are an SEM firm in Detroit). If you are in the search industry when you hear the Big 3 you think of Google, Yahoo! and Microsoft.
Speculation is rampant out there about who will win the "Search Engine Wars." Many think that Google, with its current mass and indexing abilities will win, while others see Microsoft as the dominant player, with its future integration of search in the desktop. Still others feel that Yahoo! offers the best "all around" solution, combining search with other online experiences.