Years ago when both Microsoft and Apple decided what to put into their next operating systems they had to look into the future. Picking arbritrary one from each company makes for an interesting comparison: Vista got a feature where a memory stick could be used by the operating system to speed things up. Harddrives are 10,000 times slower than memory. USB2 still 10 to 40 times faster than most drivers. Makes allot of sense. It is probably a very tricky thing to implement: the user can remove the stick at any time, and things still need to work. Trouble is: Internal memory got dirt cheap. So a complicated and expensive idea that has no future net gain.
Compare that to “TimeMachine”. The actual concept of a backup is nothing new or innovative at all. But Time Machine makes it possible that people back up easily. External drives are inexpensive and easy to use. Makes 100% sense. The TimeCapsule rip off lets show apples dark side again. But at least they did not extend it to normal drives. The value of a working backup is huge. Once people have stories to tell that TimeMachine saved their Live they are sold for good and forever to run only Macs. Maybe if hey will backup to Memory Sticks in the future …