Paid search will eclipse all other forms of online advertising in the coming years, according to investment banking and research firm S.G. Cowen & Co., which estimates that U.S. advertisers will spend $6.1 billion in paid search this year, and $6.4 billion in all other forms of online ads, such as branded/display ads and classified listings, writes InfoWorld. Starting next year, though, paid search will account for over half of all spending and will continue to increase its lead every year. By 2010, companies will spend $17.3 billion in paid search and $12.4 billion on other forms of online ad categories, according to S.G. Cowen.

An S.G. Cowen study, released last week, found that Google is the engine of choice for U.S. searchers, with 52 percent of respondents considering it their primary engine for general searches. Yahoo was second with 22 percent; MSN and AOL tied for third with 9 percent. Ask Jeeves accounted for 5 percent.

Those who prefer Google's search engine tend to be richer and have more internet experience than others, according to the study. Their average household income is above $60,000.