Not surprisingly, search advertising should continue to be the largest category, growing from $9.1 billion in 2007 to $20.9 billion in 2013. Source: C|Net News, June 30, 2008

• SEO: $1.3 billion (11%)

Source: SEMPO data via Massimo Burgio, SMX Madrid 2008

• 100% search visibility ranking 1 in natural search
• 50% search visibility ranking 1 in paid search

Source: Enquiro

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