I'm with Rik here, there are gradations and there have been developments in technology to allow higher and higher standards. A budget audiophile will love THX certifited and and that is assurance that it will sound great and be in your price range. But its not hype to take things to higher standard for big-budget audiophiles and it costs exponentially more money to improve something beyond those points technologically, extreme care in cabling, wiring, connections, heat, etc. It is as Rik said a level of quality assurace. THX Ultra 2 is nothing to be angry at it a professional level standard or a very high-end audiophile. Liking music, movies and having good sound and some clarity and 5.1 with bass is most people, they'll recognize a good system like a Bose (overpriced) for example. A trained ear, using expensive equipment and using source material like SACD or DTS-Audio, or DTS-ES 6.1 DVDs is going to notice the most. For example most people notice the difference between an MP3 encoded at 128 or 196...320 is supposedly the holy grail of CD quality, audiophiles have a service like Rhapsody or Npaster (can't remember the name) where the files are sourced from digital masters at an encoding rate of 7k to 10k. If you don't have the equipment, the wiring, the positioning, the source material, and a trained ear you probably won't notice a difference. It's like wine tasters vs. average wine drinking population, most of which know good wine.

Personally I think its great to have this certification, it gives a standard that doesn't allow a good system to go bad for movie theaters. That Camelot theater that has the Christie Digital Projector I saw ROTS and War of the Worlds on looked great and sounded incredible as it was THX certified sound. The sound blew away the other times I saw these movies in regular theatres and quite frankly blew away batman begins even at IMAX.