Aww! Thanks for reminding me of Naruto 4 to GC, just when I had forgot it ever existed, I now find myself frothing for the game, once again :'/
By the way, I played this while I was in Japan recently. Controls were so-so, but if you're really interested in Naruto, this game seemed to have a nice "adventure" feel it.
I don't really know if the game is good though, only tried it for about 2 minutes or so..