I'm gonna have to check the volume. I didn't notice a difference on water in pure volume, but at 80, +- a few does not make much of a difference for me (at 70 kilos).
But the differences in the tail might make up some of the difference in ride which I write about above. For me, it was not so much a question of looseness on the wave. More a slightly higher and more agile ride. I would guess the extra v is there to keep the looseness and ability to enter a top turn smoothly despite the tail being a bit wider. The sharper rails might be one of the things that make the board more agile.
As so often with the EVOs in the big scheme of things consecutive boards are very similar, but at the same time there is a always some fine tuning going on, to make the new boards do its thing even better. In the 80 08->09 case, all those little changes here and there seem to add up a board that kind of performs the same overall but has that higher and crisper ride which is especially noticeable in the light wind part of the spectrum.