All right. I have come to shed the light! Begone, light! *I said get lost....d'oh! why you little...*
Okay, first of all, here is what we know as of Wednesday, April 23, 2003. You can play up to 8 players using 2 GCN's, 2 TV's, and 2 copies of the game. It is unknown as to whether you can use more than 2 GCN's/TV's.
Here is the list of character's known so far:
Mario
Luigi
Baby Mario
Baby Luigi
Bowser
Bowser, Jr.
Donkey Kong
Diddy Kong
Princess Peach
Koopa Troopa
Koopa Paratroopa
Wario
Waluigi
Yoshi
Birdo
Princess Daisy
=16 so far known. Obviously some are missing....like Toad...but we shall see.
Next, it is unknown as to wether or not you can choose your vehicle, but you will be able to pair up any two characters. Each character has his own driving attributes as well as 8 items/powerups exclusive to him/her. There are also 6 general items anyone can use. You can switch your driver and shooter at any point during a race. This will obviously offer a lot of tactics to play into the game, since you may have switched to take advantage of a weapon, but then again your driver changed and thus your kart attributes also changed. It appears you have more control over the weapons and also that your shooter character can "jump" from your kart to another. This is shown in a screen where it shows Daisy jumping from Luigi's kart (well actually the princess kart, Luigi is driving) onto the Kong Kart, with both Donkey Kong and Diddy already onboard.
As for the graphics...yes they aren't jaw-dropping, but I garauntee you the animation is incredible (in one screen, Donkey kong pulls a sharp turn and Diddy out back is almost thrown off as he barely hangs on...), and I wouldn't be surprised if it ran in 60 fps in 4 player split screen as well.
Now give us LAN F-Zero!!! 29 human opponents hahahahahah
EDIT: Oh, and I don't think Nintendo is lying when it says each character will have 8 EXCLUSIVE weapons. I doubt there are clones. And this game has been in development more than SSBM, which was slightly rushed in terms of clone characters...Let's see, 6 normal weapons, plus 16 known characters with 8 weapons each....that's a lot of weapons. Unless Nintendo is lying and each character has their own weapon SET but not entirely new weapons...we shall see at E3.