I am using it to mean not complex, not busy. A simpler boxart has the least going on, as such something like http://cache.kotaku.com/assets/resources/2007/02/ff12rwboxart.jpg is very simple.
The way in which the Wii arts are "clear" is that they show context. The 360 versions are stylistic, and portray what you said above in their style. Those messages appeal to young males particularly. Showing context isn't particularly targeting children, on the other hand. A kid doesn't need context to know that FIFA = Football any more than anyone else, probably less so than the average customer. EA have decided to show context (essentially reinforcing the point that this is a football game), maybe to attract more people who buy gifts for others or to attract buyers who wouldn't normally buy FIFA.
A game I'm developing with some friends:
www.xnagg.com/zombieasteroids/publish.htm
It is largely a technical exercise but feedback is appreciated.
