Mario Multiplayer

New Super Mario Bros Wii shocked the Mario theme with a new multiplayer feature back in 2009. This is arguably one of the best decisions that Nintendo has made with the series, making the game more fun than ever before. But, it's not without it's problems. For starters, there's no online mode which is a shame, because I think and online mode would be pretty cool. If they do include multiplayer for the next Mario, then they should probably make an online mode, I mean, it is 2011. 
They also need to rethink parts of it. When playing with friends, it is very easy to kill each other by accidentally jumping into each other in mid-air, preventing yourself from moving and by knocking off other people off ledges. It's also far too easy (and tempting) to betray people and throw them off the edge and into the lava. But the biggest problem in my mind is that the screen can drag people along, pulling the other playing into unwanted danger. Not very fun. I think that Nintendo might use the Wii U's two screens to do something about this. If not, then they probably would fix the other problems as well.