Well, I hope I'm not clouding the issue too much about the GFCI's here. It looks like the one near the top on the left side is missing a wire. The curled up white wire is not really in question (except for the discoloration where it connects to the neutral buss). If the other wire (looks like a shade of brown) is the ungrounded (hot) conductor for this circuit, then where is the white grounded conductor (which I am assuming should be connected to a terminal on the GFCI...i.e the load neutral)? It's hard to determine where the brown (?) wire is going because of the label overlay on the pic.
Now look at the other GFCI at the lower right. Again, there is the curly wire (which looks to be double-lugged into the neutral buss). There is also a brown (?) wire connected to this GFCI, which appears to possibly be spliced to a white wire with the yellow wirenut (the load neutral for this circuit?). There also appear to be two ungrounded conductors, a red and a black, connected to the GFCI.
Am I missing something here? I'm not sure that any of this would have anything to do with the discolored wires at the neutral buss, but things just don't seem to add up with these two GFCI's. Thanks for any clarification you may be able to give me.