I don't think it was. The cars aren't consistent when you "walk" down the street like they are on Google Maps which implies that these weren't generated by some

I don't think it was. The cars aren't consistent when you "walk" down the street like they are on Google Maps which implies that these weren't generated by someone driving around the GTA4 world taking screen shots. It kind of gives it a sort of an uncanny valley feel. Also, what's wrong with doing it manually? That's how the real Google Street Views is generated.