You need an HDTV to experience the difference. There are also new features like PIP on commentary while watching the movie. PS3 has a built-in Blu-Ray player.
Everyone wants one cuz its the new technology haha.. Its like a dvd player but much better. You need an HDTV to see its full effect. Im not even sure you can use them on regular tvs, i doubt you can. The dvds can hold like 50 gigabytes? Or maybe thats something else. But he normal dvds hold like 4.7and dual layer ones are like twice that at the most..