I just have a feeling that it's going to be overscripted like IV was. Like with car chases, where it's impossible to catch a guy until you get to the correct scripted point. If I outsmart the AI or just get a lucky gunshot on a tire I want the car chase to be over in seconds.
I read in some preview (I can't remember which one) that most of the missions will be more free-form this time and will allow the player to choose how to approach them. That being said, the 5 or 6 heists that are the focus of the story will probably be very scripted because that's just the nature of epic heist missions. Hopefully they'll find a good balance.
It'll be fun tearing around Los Santos again...but if I have to follow another damn train....*shudders*
All you had to do was keep a few metres right of the train, CJ!