I've seen here how PS3/XBOX/PC version is and I can tell you, PS2 version is quite poor in comparison to the others.
It's really a shame, because the most of the differences don't require higher CPU capacity or something. They could be implemented in PS2 version as well.
As Forzamilan said in this forum and I agree with him, it is a way to "force" PS2 owners to change to the new generation consoles.