I missed this comCast report at the time (September 2006).
Leading User-Generated Content Sites See Exponential Growth in UK Visitors During the Past Year
“Web 2.0 is clearly architected for participation, as it attempts to harness the collective intelligence of Web users,” commented Bob Ivins, managing director of comScore Europe. “Many of the sites experiencing the fastest growth today are the ones that understand their audience’s need for expression and have made it easy for them to share pictures, upload music and video, and provide their own commentary, thus stimulating others to do the same. It is the classic network effect at work.”
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While uniformly demonstrating strong traffic growth, UGC sites are also adept at keeping users engaged.