The paid search market will more than double from $2.6 billion in 2004 to $5.5 billion in 2009, and that growth will be driven by the "four horsemen" of vertical search, according to a new study by JupiterResearch.
The study, "Vertical Search: Early Marketers Will Reap Rewards of Low Pricing," predicts that the paid search industry will evolve similarly to media markets like television and magazines: with broad-based engines spawning a host of vertical players devoted to specific categories.
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