Autumn comments: The issue has something to do with a joke made earlier in the show about William Shatner's wife. I have read that there is a pending libel issue because of this which caused Fox to take the show off their site and ask Hulu to do the same. The fact that this was the Atheism episode was an unfortunate coincidence.
If you're like me and addicted to both television and internet, then Hulu is like a bowl of cocaine-flavored ice cream with whipped cream and a cherry on top. Basically, it's a service that allows you to stream episodes from popular TV shows with minimal commercial breaks. One of their more popular shows is Family Guy, which recently showed an episode in which Atheism is pitted against hardcore Christianity (Spoiler: Atheism wins.)
But you can't find this episode on Hulu. Why?
Due to a legal matter, we've had to pull the episode "Not All Dogs Go to Heaven" from the site temporarily. We'll get the episode posted back up shortly, after the content owner has resolved the issue.
I'm not going to pretend I know the whole story. It just seems a bit odd that it's this particular episode that gets special treatment. I'll keep you guys updated when if I find out more, but if you want to watch the episode, it is available on other sites on the interwebs.