There's no enemy to overcome, no goal to achieve in Animal Crossing: Wild World. You wake up, do some chores and talk to villagers. That's it. Why it's fun we can't exactly say, but the staggering amount of personalization makes it easy to get sucked up in this super cute world. Right from the start you're given a town. Everyone's village has the same structures but a unique set of townspeople; talking to your neighbors brings you closer and often nets cool items and clues you in to what adorable animals do all day.
And it really is what they do in the day that makes them interesting. Wild World uses the DS' internal clock to keep accurate, real world time. Tom Nook's supermarket closes at 11 every night, the town bell rings on the hour and special events happen on certain days only. You'll have to balance that pesky "other" life with this virtual one or your town will suffer. Animals won't live in a town full of weeds and unhappy commoners.
With Wild World, you can hop online and visit anyone at anytime. This requires the visitor to input a "Friend Code" so no unsavory strangers come sneaking into your little world. Obtaining these codes has to be done personally via some means ofreal-world communication - in other words, there is no in-game method for sending someone your Friend Code. That is, unless they're standing right in front of you in the real world, in which case local wireless play avoids the Friend Code rule and lets you visit another player's town much more easily.
Visiting towns lets you trade furniture, clothes, or any of the 600 otheritems in the game. You can leave messages on their town board or join in on some laid back fishing ... all manner of lazy day activities. Online prospectors have already worked out daily chore schedules with other players, effectively creating an employer/employee atmosphere.