Best Mariokart ever - especially the 8 player battle mode
Grand Prix
The typical 4 different cups are still here, but there is an additional of 4 retro cups for nostalgia. Also there is a star rating on your performance. So once you've beaten the courses then the new challenge is to do it so well, that only then you can be truly called the master.
Battlemode
I can not state this enough. EIGHT, I repeat EIGHT player battlemode. Not teams like on the Wii, though there is that option, but truly each character fights on its own. I think most of my hours on this game was in battlemode. You have not felt like king of the hill until you've beaten everyone in this on hard mode. Also they kept the best courses from the N64 version which truly takes on a new life here. Most. Addictive. Battle. Ever.
Extras
There are also little missions which are designed to test your skills. So if somehow you are bored by the rest you can become a much better racer by doing these little missions. Basically little things like drive through the 8 rings in order. Shoot the.. 3 times. Do a turbo slide 14 times in 1 lap. Stuff like that.
These are the main pointers of the game that I think you need to know but otherwise there are many characters, some of which you need to unlock, plus new carts etc.
I truly think this has to be the most fun I've ever had with Mariokart in my life. You need to play this game.