Wellington
BAAAALLLINNN'
Yep, I think the best book out there dealing with a survivor's account of the events of the holocaust is a comic book.
I've read The Diary of Anne Frank and Elie Weisel's Night Trilogy (Only Night really dealt with his account) and those were, of course, powerful books. However I think that Maus trumps them simply because of the way it's told. Art sits there with Vladek and just listens to all of his stories about the years he spent barely surviving. Along the way, the book cuts back to the near present to deal with some of the issues the father and son are going through. It's interesting to see how the holocause screwed up Vladek for the rest of his life, there was none of that in Night or Anne Frank (Anne Frank for obvious reasons).
Vladek's experience during the holocaust is nothing short of incredible. It took insane amounts ingenuity and luck for him to be able to have survived. It's really a rather marvelous story, hardened by the fact that most of it is true.
Like the other first hand accounts, the book spends no time on political or social reasoning for the events, it just dives right on in.
I'd recommend it, it's a great read.