When you inventory a system, the network adapter(s) appear and have their MAC address listed in the description field. However, I don't see this stored anywhere else, i.e., in Traits. Seems to me that MAC addr is (a) is a value that will rarely ever change and (b) would be nonetheless good to be able to find if necessary. As such, it should be stored somewhere else, where it is relatively safe, versus than description, where it can pretty easily be modified and basically lost/forgotten.