IMDB recently closed it's discussion boards so if you want a similar site where you can ask questions and talk, check out moviechat.org

I hear this had happened, what's the background ?

They said it was no longer providing a positive, useful experience for the users which is a polite way of saying that there were too many trolls. I think it was a mistake. It's true that there were some trolls but the majority of discussions were very useful. It was one of the only sites other than here where you could discuss and ask questions about TV and movies, especially older and more obscure ones. They should have just used moderators to delete any offensive comments, closing the boards was just lazy.