I just got my hands on this game... and am loving it so far!
There's some new controls in this game, including the ability to rapidly jump through scenes (very Naruto ADHD) that help when you're on a time mission or trying to retrace your steps. I've already had a few laugh out loud moments with the story and characters.
There are lots of side quests, and an original story that fits into the general theme pretty well. But the good news is that main themes of the Shippuden series are there as well.
Colors, design and animation look excellent. I loved UN3, but feel that this has the type of top quality I would expect with fresh quests and battles, as well as old favorites.