Visits to consumer sites up 10 percent overall as some see traffic soar: why?

A Dec. 11 report from the web-tracking site comScore says traffic at consumer packaged goods CPG) sites rose 10 percent in 2007 compared to the same period a year earlier. The survey suggests that “the average visitor made 3.9 visits to sites within the CPG category, viewing 10.5 pages per visit, spending an average of 9 minutes per site visit.” Food sites dominated the listings.

That’s a fair amount of attention to devote to what strikes me as a pedestrian set of products. What accounts for the traffic? Presumably recipes, contests and special promitions but the comScore press release is silent on the why. In some cases it’s an easy guess. For instance, MyCokeRewards.com attracted nearly 9 million visitors, up from a negligible base the prior year, owing to visits from a contest that was cross-promoted with other media.

My interest has to do with how to draw traffic to an established site, with a pre-existing brand. And I want more than looksey-loosey visitors: I want visitors will leave registration information, or email accounts for followups. It is not at all clear from the comScore reports whether these visitors did any more than browse and depart.

I would be grateful if anyone know of a resource that ranks registered visitors to sites. It is NOT necessary that registrants pay for any service or good. I am simply trying to find out what constitutes success in terms of asking visitors to disclose their identity, and what tactics achieve these results. Thanks.