Probablywronganyway, it certainly might be the case that he was raised Orthodox, but having been raised Orthdox doesn't mean that he is currently, no more than having been raised Catholic means that I am.

According to the Wikipedia article about him, he was raised in an Orthodox family. However, he has been quoted as saying "I wouldn't say that I am a religious Jew, but I'm still proud to be Jewish." Also according to Wikipedia, he keeps kosher and observes Shabbat, to the point of not answering the phone on Shabbat.

As for his being able to play Hoffman, I think that he's a great choice. His style of comedy has a lot of parallels with Hoffman's activities, including the one mentioned by one of the other posters here that got him arrested. In addition, his thesis while at Cambridge was on Jewish Involvement in the American Civil Rights movement. So I'd be surprised if we isn't at least passingly familiar with Hoffman.