I can't think of a single person who thinks that Jon is actually dead.
You guys are forgetting that this is Martin. Which probably means Jon is dead.
Martin's reputation as a merciless killer of important characters is greatly exaggerated, if you ask me.
Ned Stark
Robb Stark
Tywin Lannister
Joffrey Baratheon
Robert Baratheon
Renly Baratheon
Balon Greyjoy
Viserys Targaryaen
Khal Drogo
These are just the dead men who were(or could have been) a king at one point in the story. I'd say Martin's rep as a ruthless killer is quite intact.
My issue is that he's spent the past two books toying with and undermining the idea of death in the saga, without killing a single major character in them. Calling him a killer after A Storm of Swords is logical, but two books later, I certainly wouldn't say that his reputation is intact.
Considering that Jon is most certainly coming back, Quentyn's death was probably the "biggest" of the past two books, and my reaction was more "well, that was a ####### waste of book space" than "OMG SHOCK". Other than relatively minor character deaths, let's see:
-The Mountain has supposedly become Gregorstein. Coming back in a different from.
-The Hound became a gravedigger. Fake death.
-Catelyn comes back as a stupid spirit of vengeance.
-Beric Dondarrion is Resurrection Man.
-Davos' death was obviously fake.
-We know Stannis isn't dead, despite Ramsay's letter.
-Brienne wasn't actually hanged, despite the tease.
-Tyrion survived a handful of "is-he-dead-oh-wait-no" chapter-ending cliffhangers.
-Theon was captured, rather than killed.
-Mance Rayder came back, since they burned Rattleshirt instead.
-Asha with a totally unbelievable chapter cliffhanger.
-"Look how edgy I am killing Jon! Nah, not really."
GRRM has said that he tries to avoid typical fantasy tropes like characters coming back to life, but he's not helping his case lately.