Regarding the word Holocaust as a Taboo
The inability to use any holocaust-related word in any normal day or (heavens forbid) entertainment related conversation without bringing down on yourself the righteous wrath of the masses.
This is a social behavior I've noticed in Israel. As far as I know, Jewish people in the US are much more calm about it (see The Million Dollar Man as opposed to The Six Million Dollar Man for a good example).
This phenomenon constraints the Israeli social etiquette in a most severe way, giving Israeli comedians a huge gaping hole of Israeli culture they cannot even touch. The comedy style of Conan O'Brien, for example, would not work in Israel, as he is famous for not taking shit from no one.
This has more implications on Israeli society than those who meet the eye, seeing as, for example, Izaak Perlman tried to conduct a session in which The Israeli Philharmonic Orchestra would play a little Wagner, but, as expected, he was Boo-ed off stage, as the sensitivity of Israel's highbrow intellectuals couldn't overcome the fact that Wagner's music was sometimes played in concentration camps. Condemning a composer because his pieces were used in conjunction with something horrific is not something I would expect from a highbrow intellectual.
The examples are quite abundant: anywhere between saying that the Armenian Holocaust is not a holocaust because that term is descriptive of the Jews' holocaust and not any other mass murder event in the history of mankind, to banning Friedrich Nietzsche's philosophy because it was adopted by some Nazis as a tool of propaganda. Although it is no longer practiced in the Universities, it is quite a popular belief that Nietzsche was either the harbinger of Nazi ideology, or that his philosophy is somehow an encouraging medium for that ideology.
Being an Israeli, and a seeing as half of my family is gone because of those horrendeous events, I can try to understand the grief and suffering of those who underwent the Holocaust, and try not to hurt their feelings. But opening another wound instead, and creating urban myths and untruths, and even banning people from performing their art is far from where I draw the line between personal comfort and social dogma.
Afterthought: Regarding Wagner's antisemitism:
I do not try to argue the point (as some of you have thought) that Wagner was indeed antisemitic, or that perhaps Hitler was indeed a Wagner devotee, or even that Wagner's hatred towards Jews is rooted in Jealousness towards one rivaling artist, but rather point out that even if he was, it should not be a reason in judging his art. If his art did include antisemitic traits, or did have an underlying layer of them, I would see it as wrong; however, seeing as it was used a long time after his death, in a completely different state of events, I cannot see the importance of Wagners antisemitism in this matter.