Apologies in advance for any breech of web etiquette with this extended post I really don't reply in forums often but I couldn't resist answering this slew of questions.
Would you say your gender attraction is 50/50 down the line, or is it more like 60/40 or 75/25?
No, I find it varies with my mood. I would have to say it is currently 60/40 women/men due to a girl I am currently admiring at my school. This does not however mean I have not noticed some of the guys walking the halls as well.
Has it varied over time since you were in school, say, and does it vary slightly depending on the season, or perhaps on your mood?
Yes, It has varied in middle school, high school, and again in college. It also changes with moods as like anything else, sometimes you just have a craving for whatever flavor you haven't had lately. I can't say it changes with the seasons though.
Has your attraction to either gender ever wavered or disappeared?
After a three year relationship ended with a girl friend I found my interest in females dropped slightly.
Do you watch as much straight porn as you do gay porn?
I find I watch both about the same sometimes more gay than straight but I find that websites that offer both such as a MMF threesome usually get more attention.
Do you find a difference between what you are sexually attracted to vs what you are emotionally attracted to, in other words, are you more likely to have sex with one gender but more likely to fall in love with the other?
Yes, I find that I am more likely to fall in love with women and just have sex with men. I also find it difficult to see myself growing old with a man, but I would like to think that if presented with a boyfriend I thought to be ready for a lifetime commitment I would accept it.
Did you always realise you were bisexual, or did you once think you were either gay or straight?
I identified as straight in middle school up to about the end of sophomore year highschool. I then started having moments where other guys started to catch my eye but quickly learned to put that aside till I was out of high school due to the fact I was in an all boys catholic High school.

After, I took some time to think about it and decided both sexes were free game and it didn't really matter.
Do you find people's reactions to be negative, even more so than if you were gay?
I can say my parents don't really mind either way. They always say as long as I am happy they are happy. My mom has taken to asking if I want to/plan to have kids lately though. As far as friends and others I have always been guarded about my private life and of the mind it would be called "Public life" if i wanted to share with everyone.

A few friends know but most are content to think I rarely date and just hang out with many different people. The fact that I act a bit childish and still play video games seems to tell people I am not thinking of relationships for some reason? Go figure eh?
Was there more pressure on you from your community/religion/family/society to deny your homosexual side because you already found women attractive?
I cannot really answer this because as I stated before I manged to keep extended family and all but my closest friends out of my private life.
Is it more common or less common for bisexuals to be 'out' to everyone?
I think it is less common actually depending. I can see a case being made either way cause if they still have hetero relationships than there is a chance they could be "Normal" and get over the "phase" of homo relationships? But I also can see how some people would not want to relate to being bi as most gay/lesbian parties believe that bi is just a short transition in making the full conversion over. I found this very annoying when one of my gay friends found out I had a boyfriend.
Is bisexuality more common in women than in men?
I think it is more acceptable for woman but I am not sure if it is more common in them.
Is it perhaps easier for women to admit to than men?
I think it difficult for either sex as there are always people who will find this offensive in some way. I know one girl told me there was an awkward period between her and her friends because of their religion and how they were raised but once they noticed she still held the same values they did just thought other girls were attractive as well most of them warmed up to her again. she did lose two friends from the group though.
If so, do you think that far more straight men are bisexual than they let on?
Probably, I know of a few guys that will mess around when drunk and the next day think nothing of it. I also wonder why so many hetero men can act amazingly gay around each other yet say they have no inclination of attraction to others? This is often very confusing to me and I tend to avoid making any comments once this type of behavior starts. If I had a dollar for every joke/tease that involved butt sex

or insertion of penis into some bodily orifice between my hetero friends. I could probably pay off a few credit cards and a good portion of school loans.
I hope these answers are enlightening and/or helpful to others.