Hi Guys

I've been asked to implement Facebook login on our company website but have a few questions that I hope some of you could have used this mechanism before can help me with.

1. At what point can I take the data from the user's profile on they have logged in using their Facebook account? I've been on a few websites where it seems to create an account on their site automatically without asking for extra permission. I've also been on other sites where you have to click Okay and then they simply pre-populate their own sign up form with the data they have retrieved from the user's FB account. Can someone offer some guidance and the pros/cons.

2. If you allow FB account on your own site are there any risks I should be aware of i.e data security issues, do Facebook track the fact we are using their login plugin? i.e will my company's name appear anywhere?

Any info will be greatly appreciated.

Many thanks