If you enjoyed the original, or even if you never played it, you will love this!
The primary focus and gameplay remains the same with a few more twists such as underwater and space modes. The solo levels are a little bit harder, which is nice as the original was a little too easy, so you wont get bored and gettting gold can actually be a challenge on some levels.
As before the multiplayer shines, this is quite possibly the best party game out there and is a ton of fun with some friens, above that you can create your own levels and let your imagination come to fruition.
Possible the most significat improvement in this sequel is that ability to download levels, this give this game nearly endless gameplay as more and more levels become available.
The graphics are nicer then the sequel and the motion controls feel smoother and more fluent, the physics seem a little bit improved. There is a much larger veriety of things to do in this sequel with the added modes and downloadable levels you wont see the end of this game for quite some time.
I would recommend this game to anyone, this is what wii gaming is all about, its tons of fun and a great party game, and for the price there really is no better value as this game is splitting at the seams with content.