Street fighter do the same thing.
how big is the NV install? shouldent SSD's do anything better than HDD's on NV?
not the install that happens the first time playing a game on your system, GT5 has a huge amount of data to be loaded throughout switching menu's, loading car data, the beginning of races etc. so the game asks you if you would like to install about 8GB of data that will decrease loading times. this is completely optional, but if you choose yes the 8GB of data slowly increases the more you play, putting a rather large chunk of your HDD towards a single game. I don't think you could do this with NV, as the game has already been released, and I don't think they can do it in an update.