The thing is, when you're a minority, there's always going to be a loud group of individuals who speak out against your group, be it sexual orientation, religion, whatever. Most of them are ignorant, and they don't represent the majority of Americans. However being as loud as they are they weild a good deal of influencial power.
Is there really a problem with homophobia? No more so than there is with racism or any other social injustice. The average citizen, and majority of people for that matter, are indifferent. Being indifferent means just that, they're not willing to fight for your cause, but they're not going to bring you down. They tend to be influenced by the loudest voice.
In the crusade for homosexual rights however, there are instances of homosexuals who are so outspoken for their cause that they alienate some of us indifferent people. I think that gets mistaken as homophobia, but really it has nothing to do with homosexuality. It has more to do with that individual's experiences with the radical actions made by outspoken members of the gay community.
You also have to remember though, in america, the good majority of the population is some denomination of Christianity. Most denominations of Christianity find homosexuality to be an unnattural practice. Once again though, I wouldn't say those people are necessarily homophobic. In fact... I don't really like the term homophobia. I think its a misnomer really, and many people groups of people get lumped in with the homophobic demographic who are not homophobic, simply believe differently from homosexuals. Just because someone doesn't agree with gay marriage, doesn't necessarily make them homophobic.
In regards to the OP, you have to remember that even though the term Gay was adopted by the homosexual community, it's not necessarily their word. Long before it was used to describe homosexuals, it had a completely different meaning. While I can understand homosexuals having problems with the word Gay being thrown around with negative connotation (as the origin of which probably does have to do with its association of the homosexual community), I think they should take into context the use of the word before being offended. Though... that's from the standpoint of an outsider looking in.
I don't think most people who use the term "gay" in a derogatory manner are really intending it to be malicious towards homosexual. I also don't understand why homosexuals embrace the term "queer" as that word has innate negative connotation. However, they seem to be content keeping that word as a label. Perhaps when people say gay, they associate it with the word queer as the negative connotation queer has. Not being used to describe homosexuals, but to say that is gay/queer/peculiar.
Anyway, flame on.