While the changes in the show were a bit underwhelming, as in Jon is more brooding and tired of fighting, to the point that Sansa has to motivate him, I do think that the changes in the books will be a bit more drastic. We will take as an example our favorite pin cushion Beric Dondarrion. Man has come back from the dead many times and he himself says "Can I dwell on what I scarce remember? I held a castle on the Marches once, and there was a woman I was pledged to marry, but I could not find that castle today, nor tell you the color of that woman's hair. Who knighted me, old friend? What were my favorite foods? It all fades.". It seems there has been some memory loss although Beric did not warg into a wolf as we assume that Jon does. We can also see that if one's will is not strong enough, their wolf's personality takes them over, like Jojen warns Bran so many times, and as happened in Rickon's case, the wolf taking over the boy. And even if he does get resurrected, how do we know that what comes back will still be Jon and not something else?