If we create the correct sized png images, rename them the same as the ones inside the profile (avatar_64, avatar_32 or whatever, im not sure the exact names) would it show to people on xbox live, or would only us see it? :/
only you would see it, because the gamerpicture is cached in their xbox as that picture not yours. Also when their xbox downloads the codes to show that picture, your picture still needs to tell their xbox the previous pictures codes, otherwise it wouldn't show anything, or the file would be corrupt.
IO looked into this hella earlier, i wanted a custom gamerpic so bad, seems vision camera is the only way to go, but those are so low quality.
Im sure the new Kinect will allow picture taking, for gamer pics.
Anywayz, heres hoping.