I've always wondered how those companies (Nestle in this case) can measure the effectiveness of such one off advertising campaigns. After all, more people might buy Kit Kats in the following days but since consumers do not buy directly from Kit Kat, it might take some time before retailers realize they should order larger quantities of Kit Kat and due to this delay Nestle might never know which advertising campaign w…
But for a campaign like this, I am sure the web and marketing teams are overjoyed if their web traffic doubles over the course of a week. That would be counted as a major win. Marketing drives to measurable metrics (like hits) and we let the sales teams worry about sales.
Also, there are analytics people using tools tonight counting mentions across the web. How many impressions through mentions is huge in the marketing space. "50 million people heard about the new KitKat homepage through news articles!" This campaign will be submitted to Cannes next year and possibly win a Gold Lion.