yeh obviously some of the code was redone to port it from the ps3 to the 360, because the ps3 was pretty much finished and they treated the 360 version as a new project, just using the models etc as a quick way of getting it finished... but because of the hardware differences used by the two consoles then it is't fanboyish to say that the 360 had to user lower-poly model's to render within the game, same for textures.
I doubt that it is entirely noticeable because im sure that square-enix want their game to look as polished on the xbox as it is on the ps3, it's just certain things are going to have to suffer i.e. fmv's and textures etc.
What i meant though was that i think it is interesting to see that the final product uses just over two dual layer dvd's, so if that is all the data of the game then im just curious as to why the dev's didnt think "hey, we could probably squeeze a little bit more out of the textures here!" and make it fit within three disc's.
I'm a ps3 owner, but think that it would be great to see that square-enix where willing to push the 360 as much as they did on the ps3.