That's correlative evidence; the top selling DVDs were the best movies on the market. They would have sold well regardless of the THX stamp of approval. The so-called average consumer presumes that if a title is released on a digital medium then it is of high quality--they are purchasing it because of the content less than the quality of the presentation. Technophiles such as we know that just because a film is on DVD/BD it isn't always perfect to the THX marker may be of help to us. But if you ask someone why they are buying a movie at Best Buy or Circuit City I can guarantee you it isn't because of the THX label. I love the idea of THX: An overriding body who ensures a uniformly quality product. But because the actual number of titles submitted to their quality control is limited the actual presence they have in the market is limited. For that reason I believe that the THX marker is largely passe for software. As a sometimes salesman, however, the THX marker is a great selling point for hardware. The consumer is given an absolute marker of quality--beyond brand-names--and have a reference point. But even that enhancement is becoming difficult to justify. My most recent receiver purchase in 2007, the Yamaha HTR-6060, was one of the first (if memory serves) to eschew the THX labeling. It has phenomenal features and sound quality, but the lack of THX certification brought the price down from its predecessor by a few hundred dollars. A reading of reviews and my own auditioning proved it to be a fantastic replacement for my Yamaha HTR-5550. So THX certification can be a useful baseline referent between products, but because it is not universally applied it loses a significant portion of its persuasive, rhetorical appeal to the consumer. There is a segment of the population who will always defer to THX, just as there are always people who prefer Sony or Bose without comparing other brands. Losing the THX branding is not, however, a significant detriment to shoppers in the era of the Internet where comparative reviews are increasingly simple to find and the consumer needs not rely on an unseen body to mark quality through unknown measures.