When signed in to Facebook.com, upon visiting Trazzler.com, you'll be automatically signed in and asked to invite your friends (a little pushy, but whatever):
Next, I'm asked whether I already have a Trazzler account:
If I do, I'm asked to sign in, completing the profile link:
If not, I'm asked to specify a username and my email:
Facebook then asks if I want to allow Trazzler to email (without revealing my email, which, of course, I already gave to Trazzler:
Finally, I'm asked for "Special Permission" to authorize Trazzler indefinitely:
I'm finally setup, with a notice that "Facebook is part of Trazzler whenever you connect":
