There doesn't seem to be a way to delete photos from Photo Stream. I understand the purpose of Photo Stream is to make sharing photos between devices a zero effort affair and is not meant as a sharing service like web galleries was in .Mac/MobileMe but this goes a little too far in simplicity. There should be some control over which photos make it to the photo stream or at least a UI on iCloud to manage photos after they've been uploaded to the cloud -- if not via Aperture or iPhoto. Am I missing something here? Is there a way to delete images from Photo Stream?