Quad Density CD-R writers?

GeoffM asks: "It seems strange that no company is making Double Density or Quad Density CD-R writers/readers. Most storage mediums tend to make these leaps. Why haven't CD-Rs? Given that CD-R media prices are dirt cheap a higher density standard would be very popular. With 2.8GB of storage and MPEG4 encoding a person could easily record full length movies/tv/home video on a CD-R that costs less than 50 cents! Are the new blue lasers too expensive? I'm tired of waiting for DVD recordable AND I'm not looking forward to the cost of blank DVD media. What's your take?"