I have an EOS 20D and have always wanted a full frame DSLR.\nI'm somewhat disappointed in the 5D mark II's new battery, LP-E6.\n\nAccording to canon\n([URL]http://www.usa.canon.com/dlc/controller?act=GetArticleAct&articleID=2046[/URL]):\n\n"Each LP-E6 battery pack has a microchip with a unique, 8-character serial\nnumber. You don't see this number on the outside of the battery, but it's\nembedded in the battery's information source. When the battery pack is\ninstalled in the camera, you can register it using a menu command. This adds\nit to an in-camera list of LP-E6 battery packs, with serial number memorized\nand displayed."\n\nThis seems to imply it would be harder if not impossible for 3rd party\nbattery makers to make a compatible battery. The supposed added benefits of\nthis new battery doesn't sound all that exciting to me. I already have a\n"collection" of BP511 (compatible with EOS 10D, 20D, 30D, 40D, 50D, ...).\nI'm all for innovation, but why can't the camera be designed to accept both\ntypes of battery?\n\nLet's call a spade a spade. This battery's main purpose is to lock out 3rd\nparty batteries.\n\nHow come FTC doesn't step in and force the company to make their system more\nopen like they did to a certain computer operating system? Or stop them from\nunfairly bundling their own brand of battery with the camera body?