Has potential, but needs work...
The graphics seem like they have improved in some areas, but slacked in others. It seems to be a step below Budokai 3. Some of the characters look more realistic now (such as Frieza, Cell, etc.) but as for the human characters (Goku, Vegeta, etc.) they don't look as real as they did in any other Budokai. The scenery is nice to look at, but the 'scenery-destruction' could use some work.
The game's controls are slightly hard to learn for a novice, even if you have mastered all previous Budokai games. Even a skilled player may still experience some control discrepencies. The game will prove to be very difficult even on the 'easy' setting if you can not grasp the basic controls.
The plot of the game is the same as every other DBZ out to date; fight through all of the previous tv show sagas. The setup in this one is to fight through the sagas in order to win back Shenron's memories. /sigh
Overall gameplay: It's ok, but I wouldn't spend too much time playing it; I'd wait until the next one comes out before you dedicate any serious time to it. You have to be a hardcore DBZ fan like myself in order to spend a long time on this game. =)
Oh...And as for the split-screen....WHY VERTICAL!!?? T.T