As the product of a country which believes first and foremost in personal liberties and free speech, I find it blasphemous that one could be criminalized for denial of the Holocaust. While it was a tragic event marked in history forever, people are entitled to their own beliefs and viewpoints, regardless of how wrong or misguided they are. Someone can tell me the earth is round all they want, but I can also say that it's flat for the rest of my life without risk of persecution; while the Holocaust is a significantly more touchy subject, it is certainly able to be ridiculed and misinterpreted by individuals in the safety of their own homes as much as they want.
As offensive and anti-intellectual as those who deny the Holocaust are, and as much as they do not deserve to be trusted or respected, nevertheless, we must safeguard the right of free speech. Holocaust deniers specifically use language or speech for their claims. Once we declare that particular speech form a crime, then we will find some other speech form to be a crime and so forth until we are close to totalitarianism.