Of course there’s no way of knowing if the jetpack is indeed real, but there are signs that point to it. For example one of the secret’s of Grand Theft Auto V involves a certain Mount Chiliad mural. In the mural it appears that there are several etchings that depict certain items, like a jetpack, an egg, and what appears to be a UFO.
The mural also seems to be drawn like some kind of progression tree of sorts, which would suggest that perhaps it could be a map of features to come, but then again this is only speculation so try not to read too much into it for now. Anyway the mural does picture a jetpack and we doubt it is coincidence that the source code references a jetpack at the same time
Now the question is when will this jetpack make an appearance, and more importantly will the mystery of the egg and UFO be unlocked in the future as well? In the meantime who else is excited at the idea of flying around the game with a jetpack strapped to their back?