Ecommerce

What web metrics should be important for ads? Should advertisers care about pageviews, visits, relevancy, time spent on a website?  How are different ad/web measurement firms weighing in on this topic? One firm, Nielsen/NetRatings, is now moving away from “pageviews” and toward “time spent” at a website.  Other firms are emphasizing other metrics.  Readwriteweb discusses it in more detail here if you are interested in this topic.