Let's examine the term prologue. That is the pre-chapter 1 chapter in a book.
So Gran Turismo 5: Prologue is to Gran Turismo 5 as Prologue is to Chapter 1. It is the setup for the main story. Prologue will introduce us to what is going to happen in GT5. It is a full-featured game, but it is merely a setup teaser. A prologue chapter is designed to grab you with a past event that vaguely ties into the main story. It does this by presenting its own short story. GT5
is designed to grab us and say, "You want to play GT5," by being its own short, but full, game.
So aside from some kids that don't read chapter books yet (would they truly understand Gran Turismo?) and Forza fanboys trying to trash GT5
for what it doesn't have (get a life) there shouldn't be confusion. The term prologue is so friggin' obvious as to what it means. It will be full-featured, but short. It is like being given a food sample at the grocery. It is small and has all the taste of the full product, but just because it is small does not mean it is not food.
So call prologue an introduction, a sample, or whatever, but it is not a demo. A demo is what I downloaded for DiRT, where I get a choice of three cars, each car only has one race it can go into, there is no progression, and my wins/losses are not saved in any form when I exit the game. A demo may not have proper graphics or glitches, and when I win all I get is, "I hope you liked the game. Buy the full version in stores now."
GT5
will give you 40 cars and 8 tracks. You have to progress and unlock/win/buy the cars, and possibly the tracks. You can go online and race with them. When you win you earn prizes and your progress will be saved and can be moved over into GT5 when it comes out. This is not a demo. This is a prologue, which is much more than a mere demo and will tie into GT5 when it is released.
I have a question for those who had a chance at GT4
. What was the pricing scale on that compared to the final game? I'm just trying to guess at the possible price.