A GameFAQS user went to their local GameStop and played the demo of Metroid Prime 3: Corruption there. He discovered something interesting, and here is what he posted:
Here’s a part of the game that I had no idea even existed. If you accomplish small tasks in the game, you are awarded with bonus tokens. These tokens come in four colors: Red, Blue, Green, and Gold. Red tokens are given as you scan a certain number of enemies/items. Blue tokens are given for scanning lore and accomplishing side tasks. Green I believe are when friends give you vouchers, more on that later. Gold tokens are given for beating bosses on various difficulties. You use the tokens to unlock hidden content in the extras menu. The final type of token is the “friend voucher”. Basically these are given for accomplishing some type of cool accomplishment in the game.
For example, when I beat the boss, a gold token flashed at the top of my screen saying it was for killing Lord Beserker. At an earlier point, I saved a GF trooper from being killed by two enemies. I was given a blue token for that one.
I also obtained two friend vouchers. In one case, I saved a GF trooper from being sucked into space. In another case, I killed 100 small bugs in a room before leaving. According to the game, you apparently send these “achievements” to your friends, and they give them green tokens. I think it’s a level of competition between friends to see who’s unlocked the most “achievements”. I was interested in this since there was a “Friend Roster” option and a “Configure Wii Connect 24″ option on the menu.