I played King of Swing to the end and liked it so i've been anticipating this sequel for a while. Here's my thoughts on the game so far. I've just completed World 1 at this point.
The new art style really isn't sitting well for me, all the muted colors just make the atmosphere feel dead to me, i really miss the cartoon-y style of the original.
The gameplay is pretty much exactly the same as the original so if you didn't like that one i'd advise you to stay away from this one. I have to say though that this game is exactly what I needed for me DS right now. It's a nice pick up and play style game where you don't have to invest much brain power during play time and still have fun, turn it on, go through a level or 2, turn it off. I already know I'll end up playing through to the end like i did with the original, then after that i'll probably go looking for all the hidden coins and trinkets in each of the level.
The mini-games are also lots of fun, i don't understand why they didn't implement a simple online ranking board because these mini-games deserve it.