To echo @adambard, I would've given this a shot as well if you hadn't requested my FB login. I'm very protective of using my FB credentials on a site I don't kn

To echo @adambard, I would've given this a shot as well if you hadn't requested my FB login. I'm very protective of using my FB credentials on a site I don't know much about (probably an irrational fear, but I know I'm not alone.) You will get more signups if you offer alternatives, vs. trying to convince people you won't abuse the FB privileges. Just something to consider.