Cool. I guess I am in the minority that hopes Snow is dead. I like the finality of the series and feel cheated when people get brought back.
I agree on the general point that dead characters should stay dead, and the diminished importance of death has been one of the many problems in books 4 and 5, but killing Jon Snow would be silly at this point.
There are so many deaths in this series that it's hard to keep track of. The only resurrections that I can recall are Beric Dondarion and Lady Stark. Everyone else stays dead. GRRM likes to play with the readers by making us think that Arya and Jon are dead at the end of their chapters, and finding out that they were merely KO'd, that doesn't really count as being brought back from the dead.
I don't mean just resurrections.
What you call GRRM playing with the readers is what I call cheap soap opera cliffhangers. It's even more ridiculous when the book ends without explaining their fates, and the next book doesn't come out for years. There's Arya, Jon, Asha, Brienne and likely others that I'm forgetting. Aegon also "came back from the dead", if it's really him. Martin also led readers to believe that Davos was dead in book 4. It's understandable due to the nature of the different viewpoints, but still diminishes the feeling that characters could die at any moment. Also, while characters stayed dead, no one of actual relevance died in the last two books, unless you're counting Jon as dead. Quentyn doesn't qualify, in my mind.