Blue-Laser DVD Formats Wars
killmore notes a story running on ZDNet talking about incompatible blue laser formats of Blue-Laser DVDs which can store 36GB of data. The new format is from Toshiba & NEC and boasts backwards compatibility with the current standards for DVDs.
An empty disk allready has tracks on it which are followed by the laser when writing. Those track are different for different media, so you cannot write a cd-r format to a dvd-r.