At least the faction leaders who had cheaters in their ranks should be informed, that is a
bare MINIMUM.
Otherwise, the only "punishment" for cheating --
and here we had people cheating for at least 3 weeks -- is having to buy a new Warband key, around 5 (1 less pizza next month), not exactly a harsh punishment, nor anything that people would learn from, they'll just wait for an update on the hack or try to find another hack. When someone is caught they'll also 99.9% change their nickname, leaving behind no trace (except an IP for admins but that doesn't exactly justify anything for the community, plus most people have dynamic IP's anyway). Sure they lose their character and playtime invested, but if you've cheated your way through its not like they cared about the amount of time invested, they wanted to do it as fast as possible with as little effort as possible.
Cheaters should be shunned not protected, passive action like this is what leads to mass cheating.
Legally speaking there is no privacy concern in releasing character names unless they can be tied together to actual real names which again would lead to actual real addresses, do your research, protect the community.
I say we hunt down these heathens and lynch them!