Yet another Wiki topic (FYI, I have a new strategy page under heavy works, which might actually be usefull for new/intermediate players)
There is this Level page which is accurate to describe the mecanism, somewhat interresting, but rather poor game play wise.
Also it does not deal at all with other XP bonuses (It really smells of the old alpha days, when the only XP bonus came from higher monsters killing).
So should XP management and bonuses be handled there ? Or should we create 2 different pages, one describing the mecanism (this page), the other one describing the strategies around it ?