Sorry I don't own this one but at the office we've seen that sort of cracking. Our IT guy has some nice plastic paint he sprays on it, dries over night and then it's back in service for years. Some think he's too practical and uncaring about aesthetics. He does however now have a black and a white color choice.
I just got my GS3 through T-Mobile about a month ago, and just this morning noticed that it looks like the back battery cover has cracked. It looks like when you're going down the freeway and someone in front of you kicks a rock up and it puts a big kind of star burst cracked in your windshield. I took a picture of it to show you what I mean. Has anyone else had this happen?