Yep, Sidney's nose went 'pinky' his first winter and though it got darker again this past summer, it never really quite went back to the full 'jet-black' he had as a little puppy. Well so far into this winter most of his nose is back to pinkish. I think that all dogs with dark noses, experience some lighting of the pigment during the longer dark winter months... and to, all dogs' noses will lighten with age. The degree of pigmentation loss in either case, I think, is determined by the dog's genetics.
I believe the term use to describe the color of the nose, lips, and eye-rims of a dog is "black points"... and Golden Retrievers are supposed to have strong black-points.