I've looked into this subject this morning, because I'm interested in the details too. Here is the stuff I dug up:
ULSD has an added lube "rating" but it seems to be a "drier" fuel than LSD, which means it does not (or should not) lube as well as the old stuff, but it is not appearing to be harmful to the internals, as I have about 2500 miles now on the new ultra low and I have seen not a bit of driving difference, fuel seepage at seals, or additional build up on the freshly-cleaned turbines. Will it need an additive? Not as far as I can see, because it is simply a "cleaner" fuel and lube, leaving less deposits, not reduced protection.
It appears, however, to NOT be good for the new engines MAINLY because of the emissions systems, and honestly, I cannot find another reason why it would hurt a diesel motor of any age, again, besides the emissions systems of new trucks made after CY 09-05 or so.
EDIT: "hurting" applies to using the OLD fuels in the NEW engines, not the other way around.
That's all I know so far, I'll report anything else as I dig around this morning.