A GT5 prologue demo is heading to the ps3 on the 20th oct free on the Playstation online store.
Its probably a single player demo but it,ll give us a taste of the power of the ps3.
So in a way its a demo of a demo.
Take the graphical test and pick the game pic from the real pic
http://generationdreamteam.free.fr/Quizz.html