His new artistic technique appears to be tracing photographs, but the work is no worse for it. He uses photos of the worst atrocities in Auschwitz, repeating them over and over, moving in for close-ups of peoples' faces, peppering this with famous and less famous anti-Semitic quotes from people down through history. It's certainly powerful, and he's found a great way to express his feelings.
I think it's interesting, and certainly worth a read. But Sim misses something. I'd say it's the artist's responsibility, not to do a piece of work about the Holocaust, but to fight and make sure it doesn't happen again. To get out there and join anti-racist and anti-fascist groups wherever possible. Art can change peoples' minds, obviously, but it's their job, and everyone else's who feels the same way, to get out there and work for a better world also. The fact that Dave Sim thought to put his own name above the title shows for all his interest in making art about the Holocaust, he's also equally bothered about keeping his name out there.
It's also incredibly sad that when this comic emerges into the world, the only Jewish state in the world, Israel, is committing acts of similar indiscriminate carnage and war crimes upon another group of people who the world is demonising the same way it demonised the Jews. Buy this comic, by all means, but remember reading it isn't enough to make the world safe from future Holocausts.