The photo stream is the worst designed feature I've ever found in any version of Apple software going back to the 1980s. Instead of syncing the camera roll amongst all devices, it makes it nearly impossible to delete photos. I took a number of sample photos around the house tonight. They synced to my macbook, and after trying for over two hours, I've found a ridiculously intensive way of deleting them.
If you disable photostream on just the iphone, it will reload the images as soon as you reenable it. If you disable photostream on the macbook, it will reload the images as soon as you reenable it. If you go onto icloud.com and delete the photostream from there (That's nice and simple for a company that prides itself on "it just works" - go to a website inaccessible from idevices...), it still will not work. You need to disable photostream on all of your idevices, and delete the photos from iphoto's photo section, and delete them from icloud.com, and then reactivate the feature on each device, one at a time.
Be careful snapping photos. If you don't delete bad shots in the first couple of seconds after taking them, you'll be up half the night trying to do it.
This feature would be quite useful to those of us who may not like to have to synch the camera to upload photos, etc.
iOS 5 makes it infinitely easier to go back to cords.
