You guys must remember that Polyphony digital is a small team, Sony owns them and if Sony won't increase the size of their team then there is nothing Polyphony digital can do. Each cars has an average of 200k polygons, and takes 6months of one persons time to make. GT5 is the best looking racing game ever and it takes a long time to make perfection.
EDIT: Plus the fans have demaned damage and that will take even more resouces to make, plus they don't want to do the same crappy damage that was in Forza or many other racers.







