Very good game, but a little exaggerated...
People could have cared less about the gameplay when first looking at it, even Gamespot and big corporations were that way(don't deny it, that's the first thing you thought, that they are in the same game). However when it came out it got low reviews. Why? Because while it is a very good game, it isn't as good as everyone was hyping it up to be.
The game has INCREDIBLE graphics. I was in awe at my television seeing how much the characters just popped right out.
The sounds were also very good, very realistic for sure(although peach still sounds like she's speaking to you through a wall). The only thing is in fencing, the wiimote produces a jabbing noise that kills off the one on the television.
Now that I've gotten you in a good mood, time to break down to the negatives.
The game's controls are easily it's biggest flaw. For example, when running it is required that you swing your arms like a nutjob. Another thing is the controls for every event are either so easy that there is no challenge involved whatsoever, or it's too difficult to pull off and there is no way in heck you'll ever succeed at the specific game unless you waste massive amounts of your time at it.(such as 3-4 hours attempting the exact same task again and again). Not to mention true, you are going to look absurd playing most Wii games but absurd you look while playing this game is off the charts(I recorded myself rowing and watched it... I looked like I was "thrusting" toward my television).
Back to the positives though, the cast of characters is definetly quite impressive, and most of the characters stats are just like their's in the games. However some, re off. Such as Peach easily being way better than Bowser. That can't be right, how else would Bowser capture Peach if she has way better physical fitness than him(and possibly even Mario?!!!!). The game also makes Chubby boy Eggman very fast. Other than that they hit the characters spot on.
Overrall, I think I've stated what I needed to. Great game, deserving of much anticipation and wanting but the reason it wasn't getting as good of ratings as it should have gotten was because everyone anticipated it a little too much, when it didn't reveal much of itself. I think it's a definite play, but if you're deciding between this and another game, and you can't decide what to buy: then rent it first and see if you like it.