Why Little Search Engines Can't

There's an old adage that a rising tide lifts all boats. But in the search industry, where the tides have been rising like crazy, the biggest boats are rising a lot faster than the smaller ones.

Ad spending on the Internet has been booming for the past year, and the fastest growth has been coming from search-related ads of the kind found among engines such as Google and Yahoo!.

Google's revenue, which is nearly entirely generated from search-related advertising, grew 93% in its latest quarter, while Yahoo!'s revenue, a mix of search and branded ads, grew 55%. ...