For example I just got Volkund (sp?). It is a heavy armor mask with -20% cost to three spell schools, however, it just so happened that those three magic schools were the ones that I used and therefore the highest level. If I had three other magic schools at the highest level would they have been on the mask instead?
Also, I remember artifacts in Oblivion would scale to the level that you obtained them - here is an example - http://www.uesp.net/wiki/Oblivion:Chillrend - Does this happen with artifacts in Skyrim as well?
Thanks