Well, taking it one step at a time. That's great though, glad he took it well. Just keep at it slowly man, if you don't feel ready to tell your mom, don't tell her. If it's endangering to you, don't say anything. But honestly, put it this way: tell her when you're ready to, when you're sort of in a position to do so, worst-case scenario.

Well that fact that you're bi rather than all out gay might lessen your mother's reaction.

It great that your brother is cool.

When I told my mom for the first time that I had an interest in boys, and stating I was bisexual - She freaked out herself; She made me force myself into believing it was wrong, and that I was straight.

It really depends of your age when you tell them, I told them when I was 15 - and now 4 years later; I am telling them very soon. It is not a bad thing to tell your family or freinds; but they can have a different approach on it. If your family member(s) or friends have a problem with it, then they obviously either don't count on you, meaning they don't love you as much as they think you are; or they are just stunned and want to talk you out of it - but on the other hand there are families, and friends who accept them; but as you said your case, I would ensure you do NOT get forced out in what you believe and feel in - Unlike me, it was a hell road.