En el edit pone que no es el primer mapa que hace, pero es la primera vez que lo presenta de esta forma. Así que creo que con esto hay suficiente para ver que NO ES REAL.
Two stories published on N4G.com claimed the 'Official' GTA IV map had been discovered, misleading numerous gamers into believing it to be fact.
The truth is the 'official map' is actually an extremely detailed fan made map, created by 'GTA IV Dude' on GTAForums.com from the outline on the GTA IV website.
here is what he has to say on the topic:
"EDIT: Sorry for the fuzz guys, I just had to see all the reactions, this is not my first fan map, but it is the first time I present a map like this. I hope you´re not upset with me as it wasn´t meant to be taken deathly serious, I hope you enjoy the map though!"