I have a site with several subdirectories. The subdirectories have different niches and I have placed them there on a site with good PR just to get the benefit from the high PR at the beginning of the launch. After a while I have a domian pointing to the subdirectory and then I redirect all pages to the new domain. Not sure if this is the right way to go but nevertheless, this is what I have done. Now, on the main site with the good PR, I see ads that has to do with the subdomains also so it seems that Google takes whatever in on the site as a whole and displays the ads sitewide. Anybody else have experienced this?