I don't really care how long it takes. I'm very excited to see what Rockstar will do with the next-gen consoles. The size of the map will be tremendous, and I hope they include multiple cities like SA. They should (and probably will) bring back Vice City, and if was thinking maybe New Orleans would make a nice location as a smaller town aside from the big cities, even though it's not that close to Miami.
I'm leaning towards the fact that R* may have heard people's wish and complaints. On SA for PS2 the map felt like you actually had a concrete destination. There were 3 cities to travel to and from.
V's map is great. Very nice to look at. But only one city and a countryside you just do a big loop around is kind of =(
GTA VI needs more than one city. More than 1 main airport. To do this however they will need a map that is 2-4x the size of GTA V's entire area with about 50x more detail.(Phew get crackin' R* lol) Within the next few months they will no doubt already have a location set internally and extremely early map designs being made. This was the case with IV to V. V ideas started not long after IV shipped. Let's hope for the best.