It's something that is worth careful consideration. It should only be done when you're sure about it, and only to the people you choose. No one else generally has the right to decide that for you. If you're in a position where it might put you in serious danger, don't do it. Don't do it to people you have reason to believe would react badly (and again, might put you in danger) – but in the case of friends and people you're going to be around for the foreseeable future, it's worth thinking about. If people drift away from you because of your orientation, you're better off without them.
Coming out is one of those things that I don't think needs to be to everyone, no matter what. Some people will never accept it and won't deal well with it, and it will just upset you, them, and could put you into danger. But I do think it's important to be visible and to let people know that in fact they are around gay people, that we are not an invisible population, and that we have every right that they do, to pursue love and enjoy life. And perhaps most importantly, that we have no intention of being silent or invisible or going back into the closet, or staying in there – even if some never "come out" per se, they can still go to the "gay ghetto" or a club and be themselves, and they should be able to realistically expect that.
The gay community is not perfect, and there are widely varying opinions of it, and widely varied ways of people living in it or leading it. You'll find your niche somewhere and, at the very least, the community does tend to come together to protect its own in the worst scenarios. It doesn't necessarily always support its own though, and you can't always count on any community to help unless you know that specific community very well.
But I do think coming out, at least to some people, will make things much easier. I do believe it's worth it, for a number of reasons, and I do think it's important to know people enough to know whether or not they can be relied upon in the long run. If you're going to call someone friend, they had better be willing to stand by you, and you deserve to know that for sure.
