just for arguments sake, if one really wanted a hub style slot, then the choice is compactflash. it's a 'real' ATA interface, is sturdy, available in sizes up to 100GB, has sd adapters, and people who have more advanced cameras also have CF and not SD. and we havent even mentioned sony people with their funny sticks. so back to square one, it's all about "what are my devices like" and "how big can it get".