I agree with you on Tony not actually planning to kill Ralphie, Lucky. It just got out of hand.

Point taken on the discussion of previews, too. However, you must admit the quick glimpse of Tony talking to Johnny Sack looked pretty ominous:

Tony: "You got nothing coming to you, you or Carmine."
Johnny: "You sure you wanna go down this road, Tony?"

Now, it could've been harmless and maybe Tony will turn around and reply, "No, you're right, Johnny. I don't wanna go down this road." But at least the potential is there for a hairy finale'. However it turns out, I don't think they're fooling us in that exchange. I.e., I don't think Tony was talking about sharing a Happy Meal with Johnny and Carmine. You gotta' admit they at least know how to whet our appetites!