Personally, I can't see Jon or Dany dying at any point. Yes, this show loves to kill important characters but always for a reason that adds to or complicates the story. Without Ned dying we don't have a War of the 5 Kings (at least not the same war), without Robb dying we don't have Jon ascending to power so he can fight the Others. I know lots of people see Dany's role as the one to come, beat the Others, give Jon and heir, and then die somehow but that has been clearly shown to be Jon's destiny while Dany's is to rule. Dany's death would also clear Jon's path to the IT, but as many people have said Jon (probably) doesn't want it and likely (in my opinion) wouldn't be good at it, or at least as good as Dany. Killing either at this point feels like it would be mostly for the shock value, which seems out of character of GRRM if he has any say. Also, as I've seen mentioned, GRRMs original plan from 1993 says that Jon, Dany, Arya, Bran, and Tyrion will survive. Yes, i know that huge parts of this original plan have changed drastically, but never have those changes effect the overall main plotpoints of the show. Yes, Robb isn't betrayed at at the red wedding, but he still dies, Jon and Arya aren't in love, but they still have a special connection, Sansa is not pregnant by Joffery, but she still regrets choosing him over family etc. They haven't killed any of those main 5 yet either, which gives me hope that the writers are attempting to stay true to this point, especially because it seems very central. These are 5 main characters, the reason we see so much focus on them is because we are intended to see their journey from the start of the series to the end, or as GRRM says "growing from children to adults and changing themselves and the world in the process". I can also think of many other way that the ending could be bittersweet other than the death of one of the main two characters. Anyway, this might all be wishful thinking but I hope that if they do decide to kill of Jon or Dany they at least make that arc rock solid. Pretty disappointed with the writing this season and don't want any of that with such a huge event.