Some of the SD card classes, and software copyright protection offer the ability to already replace DVDs, see SD Standard Overview » Speed Class, and we are at the cusp of the most performance SD card being cost effective, and one may argue based on the highest specifications of the Blu-ray disk both in capacity and performance overcome, if not, equate the performance of the Blu-ray disk. So why not the shift? Well, one has to make new drives to manufacturer players, produce read only cards, and so on. Also, why have the large player device all together? Many Televisions are equipped with inputs for SD, and even if they are not, there are very small readers today, which you could, add either infrared (IR), Bluetooth, or WiFi. There’s the next generation. I wouldn’t get to hung up on those Blu-ray disks for long. I did have stock in SanDisk, but had to sell it to pay the bills.