If he doesn't die it could have made a great plot for another season. He and Carlo jumping to the Feds and then testifying against Tony and New York would have made for a good ending in my opinion. Imagine Chris alone could have sunk the entire Soprano Family but with Carlo and his close ties on the dock and construction to New York the take down would be epic. I also think with that happening and the weight of it all on Tony to survive he flips and pulls a Joe Massino.