You know what? F**k it, I don't think he's dead at all. The more I think about it, I don't think it'll even be a case where he needs to be 'revived', because for some reason, some way or another, I think he's still going to be alive next week.
It came out of nowhere with not much lead in, and seems completely out of place with the story so far. Just like Kagura didn't really kill Erza at the end of 314 when they had that blood splash, I think somehow Gray's gonna still be alive.
Just a really cheap way to elicit a response from the readers, is what I'm expecting. I have not a shred of belief that he'll die for even a moment