WiiU need some type of Achievement/Trophy system

[sethnintendo]

Shadowfest3 said:

sethnintendo said:

Nintendo already has an achievement system called stars and coins. Collect enough of them in one of their games and you unlock hidden levels, items, etc..

This must be for the 3DS cause I know it's not on the Wii.  Can you give me an example of how this system works, meaning, do you find a star or coin in the game or do you have to do something to earn the star and coin?  Thanks!

NSMB Wii get coins and unlock levels.  MK Wii get stars to unlock more classes, karts, characters, etc..  Basically, what they have been doing for awhile in most if not all their games.