Looking at some of the earlier reviews I have to wonder if the reviewers have actually understood the book. Kershaw doesn't rehash the 'Hitler as a lucky non-entity' argument. He shows (again and again) how Hitler, through his hard-won dominiation of the Nazi party, coupled with his undoubted genius as an orator, came to power in Germany. The early chapters on the unique social and political conditions within Germany which allowed a demagogue like Hitler to prosper are worth the price of the book alone. Also, the charge that Kershaw is 'woolly' on the root of Hitlers' anti-semitism is deeply flawed. No-one can acurately pin-point what made Hitler so rabidly anti-semetic without resorting to cod-philosophy, which is exactly what real historians (like Kershaw) avoid.
Hitler: Hubris is not only the best book on Hitler I have ever read, it's the best book period.