Note: Not an employee of Magento... for a previous reply
Good question. Not one that I can divine since I'm not the Great Carnac the Magnificent. I've tried waving the envelopes in front of my brow but keep coming up with "Variable Undefined, Call to a member function on a non-object".
I have no problem with making image files "group" writable (for example my current preferred hosting provider runs PHP with group privileges so it's more or less necessary), but I definitely question the wisdom of making them writable for "others". Why not 664 / 775?
This is not working for me. I've updated the directory permissions to 755 but not able to load images in the admin under Products section.