Was you and about yesterday, so could only do a brief update on the Monster Hunter PS3 story, but here's the latest news. For a start the PS3 version will get full camera control via the right-stick, making keeping an eye on the battle a whole lot easier.
There are some comparison screen shots on [Andriasang], it shows the increase in smoothness but the lack of detail is pretty clear (rather like the Xbox HD update of Soul Calibur I was playing recently, neat but not really pretty).
Finally, here's the video:
Basically, when this update hits the west, if it doesn't turn both Europe and America into monster slashing maniacs, there really is no justice and since the game can be carried on on your PSP, it can't do much harm for the portable platform.