When I use facebook connect how much access do I have to the user's friends?

So, if you sign in using facebook on my website, how much access do I have to your frien开发者_运维知识库ds? I am asking this question because I want for example to know if a user asks me a question about his/her friend, I can go through their Facebook status messages for example and tell them the answer depending on parsing information but do I have access to the user's friends information or no? (And how can I do that if it is possible in another way)

Note that the Facebook API has recently changed (it's now the "Graph API"). As of now, you go to http://graph.facebook.com/username/friends after authenticating with OAuth. As always, there will be copious libraries to help.