Learn that Triple JUMP!!!
The coolest one would be the design of it, going back to super mario world's walk to world design. The animation is fantastic to say the least, everything you'd expect for wii's superior games. Colorful and eye popping isn't the only thing you'd come to expect for this platform revolution.
As you can tell when it comes to platforms no one can do it better than mario and luigi (I'm talkin' to you Little Big Planet) now with some more allies along the way you guest it two toads? "which i'll admit is a little lame I was hoping that they could include peach and go back to the super mario 2 roots where everybody had there own special power but I came to realize, it's a super mario game who are they going to save." Now for the first time 4-player co-op which I haven't personally been able to play but looks like a blast. A fun addition they've added to gameplay is not only can pick up items you can pick up players (Be warned when you let them go they tumble down to what a might be unwanting and wrongful death.) Being that this game is difficult if your not a veteran it's not shameful to be carried on the hard parts. Speaking for myself I have a 5 year old nephew who loves this game but couldn't move and jump at the same time so I carried him threw world 4 to world 8 tough but do able it gives a fun fresh perspective that I've never been able to expeience until now, and I've been playing super mario since I was 5. Back when mario were rivals and not ice skating together.
I'm rambling moving on, the game is long like really long. If that's not too believable and brief there's a world 9 and the only way to play the levels is to collect all the star coins in each world for each level. Which means world 9 level 1 you must collect every star coin in world 1.
Veterans you're going to fall head over heels for world 9. especially level 7 my favorite. Lets see looks cool, can throw things, 4 player co-op, oh star coins if you don't know there are three star coins in every level kind of an insentive to play again.....and again and again. The Items are too much fun although they could've been better. Ok so theres the fire suit(tradition), ice suit(same but freeze baddies), penguin suit(shoots ice balls swim better and slide over even water), propeller suit(easier version of leaf suit), mini mario(run on water slower fall rate longer jumps), mushroom(classic), and the oh so short star. I really wish they would've invested more time in the shell suit or even suprised us with the tankuu suit but I'm not complaining.
Now I'f you've palayed the classics you'll still need to master some new moves in mario's arsenal. There's the wall jump, triple jump, butt bounce(or ground pound), and my favorite an additional twist after you've jumped tricky to time fun to master.
In conclusion (since I could go for hours) if your a fan of platformers or looking for a bunsh of 4 player fun it's a no brainer, be warned if your new to the series expect to get spanked in the later stages but if need help you can always learn to mimic the super guide(luigi shows you how to do the level if you die 8 times in one level) or do what I do and unlock the videos of super skills. theyre's a reason they'res over 3,000 reviews.