I was having a debate with a friend on an issue related to adsense stats. Assuming there is no ad unit or url channel tracking enabled, will adsense "page impressions" increase with inrcrease in the number of adunits or will it remain the same irrespective of the number of ad units in a particular page?
Found the answer myself in the adsense support site. "Page reports will show an impression every time a user views a page displaying Google ads. We'll only report one page impression no matter how many Google ads are displayed on a page. For example, if a page with one half banner and one vertical banner is viewed once, we'll display one page impression."