To help you get the most out of your mac!
Deleting an image from Photo Stream in Aperture removes the photo from Aperture’s Photo Stream view, but does not remove it from Photo Stream on other devices.
See the original post here:
Aperture 3.2: Deleting from Photo Stream does not work after upgrading to OS X Mountain Lion
The outside of the box said "Windows base machine or better", so I bought a Mac.