Hi!
I'm fine with a link to the wikipedia page, but why do we have to duplicate that information on the DF wiki? That stuff takes server resources, and it has almost nothing to do with actually playing the game.
Well, the other wiki is not really within our control. It contains information that is really not interesting for players, even those who want the flavor, while information we will find very interesting may be hard to notice.
Secondly, you can add information as to "this is hinted at in the game by xxx" thus pointing out weak connections between game features and real life aspects. For instance, the relationship between DF iron, DF steel, real life iron and real life steel is actually real life information (you don't need how real life steel works to use DF steel), which can be highly informative for you and which is not found in this format in the other wiki.
Third, some of that information can also help with the suggestion/discussion threads here. Take the steel example above - placing DF iron and steel into the correct relation to real life iron and steel (and also real life bronze) can inform people about things they should consider before discussing the traits of iron, steel, and maybe bronze in the game.
As for the elf/human/dwarf quality system, I consider it a really stupid idea, especially as it endorses one particular way of viewing and playing the game, which is not the only way to enjoy the game.
Deathworks