Manual mode gives you the ability to finesse your slides with a bit of countersteer. Absolutely essential on longer, banked corners, of which there are a lot. Automatic mode is an all-or-nothing proposal so it's harder to really nail those corners tight.
So far I prefer karts (gold sparks FTW!) with LOW drift. These are easier to start your slide ahead of the turn, then finesse the countersteer to nail the apex perfectly and zip right out with the gold sparks. High drift cars turn too fast and it's tough to keep your line. King Boo is lightweight and has pretty low drift so I'm rocking him for the moment. I see Birdo made it into the game this time around so I wonder how she handles.
The problem with multiplayer is that people know to aim for the apex with their items to cut you off. When you're really trying to nail the line, you're pretty open to getting hit by whatever. For some reason, the bananas seem especially effective in this iteration. The rear-view toggle on the A button is deadly!
I played a LOT on Kart on the DS version and I think MKW is a great improvement. It's basically MKDS2.
I still have yet to check out the battle mode.
My friend code is over at
SCP if you want to play.