Are Hitachi and IBM Microdrives or Seagate 1″ drives considered CompactFlash?
Yes. Microdrives and similar products conform to the CFII+ specification are usable in any slot that takes Type II CompactFlash. Advantages of rotating media devices are that they are much better priced per megabyte. Disadvantages are that they are somewhat fragile and don’t perform as well as high end solid state cards.