For the record, the reason this happens is because people stop buying memory cards after a while. Personally, I've got like 5 different SD cards already. Every new format that they use in devices is another type of memory card that you have to buy. Since the flash memory lasts a long time, they needed to come up with another way to make money.Â
In a perfect world we wouldn't need more than CF, SD, and microSD, but with all these other formats (like my xD memory for my digital camera, or Sony's own Memory Stick stuff) things are really way too complicated.