This is a great idea but there are only few italian persons that can talk english... The topic written in italian talk about a very old question that I've posted in the forum some years ago where I answer if someone has some useful links to give me ;-)
Obviously the preferred language to use in the forum is the english ;-)
I think discussions in forums and blogs or in social networking sites should be in English, so that people can easily communicate one another and there wouldn't be any difficulty while responding to the messages sent by others.
There's a saying:It's impolite to speak in a foreign language with more than two people present when the other people don't know the language. Sometimes it is unavoidable.