AdCritic, the popular Web site that featured a large archive of television and radio ads, has closed its doors citing the difficult economic environment. Although all the media was recorded and encoded using PCs, AdCritic delivered its content exclusively with QuickTime, after finding Apple’s technology to be superior to that of competitors. AdCritic says it hopes to be able to launch again down the road. In the mean time, fans of the site can purchase discounted AdCritic merchandise.