Aperture, or the Mac, is corrupting CF cards

I've been using Aperture since the beginning, and pro CF cards as well. I have a Nikon D3S and D300 and three Macs (a mini, a MBP and a 24" iMac), and all experience the exact same problem.

Starting in August or so this summer, I would insert the card into my card reader, and it wouldn't mount. Occasionally, it would mount after inserting and removing the card reader several times, but then that didn't work either. This has happened with different brand cards, with different card readers on different Macs. NOTE: I bought new card readers, and they would work for a few weeks without a problem, and then this would start happening again ... usually, during the import into Aperture, the card would suddenly eject itself and I'd get the error message.

Then a couple weeks ago, while deleting the files from my card, the files did not delete, and now my camera tells me I have a damaged card. And as of yesterday, I now have two damaged cards!

Very frustrating, and not sure who or what to blame, or where to go. I gave up on the Geniuses at the Apple Store, as too often, I would just get a blank stare.