Some pictures stored on the server got scrambled recently, most likely by the avatar upload. I found four cases of this: Big Daddy Snorlax's avatar, nick15's avatar, yoshi1001's profile picture, and my own profile picture. I'm sure there are more. There is a way to fix the scrambled image. Re-upload the image and it should be fixed. I did so, and my profile picture is no longer scrambled. You might want to try it yourself.