With the advance of LGBT rights, it is my opinion that orientation should be a mere factor of a story, rather than the leading cause for one. Sit and think about the last novel you read with a gay character that wasn't overtly camp, though, and you may be stuck for an answer.
Modern writer, Sarah Waters, writes gay characters well. The characters' orientation in Waters' novels are incidental. Stories happen to them because of who they are, not because of what they are.
Oscar Wilde wrote about gay issues to push the boundaries, to give homosexuals a voice in a society that censored them. Although giant leaps have been made and milestones, like equal marriage, have been achieved, there is still an issue with representation. I don't write gay characters and that isn't for any specific reason; I just don't. I wonder, though, if I should write characters that aren't straight. As a member of the gay community myself, do I not have an unwritten duty to forge a representational figure in literature?
This is the question I have been asking for some time now. One day I may write one and find my answer.