This is an interesting thread!
So, original post was about religion and homosexuality. So, I'm going to comment on that aspect. (Sorry for the long post...)
Basically, there are about three levels fo this "homosexuality is sin" debate. At the top layer (and probably the weakest argument), you have those who consider scripture to be infallible, and who find clear scriptural evidence to support their claim. To this argument's credit, it's almost irrefutable that Paul considered homosexuality to be a sin (Romans 1:26-27). There are a few references throughout the Bible that have traditionally been considered condemnations of homosexuality. The Romans text is probably the most direct.
However, this layer of argument is (IMO) one of the weakest. First, we're not Paulians, we're Christians. What Jesus said takes precidence over anything his disciples and apostles said. If there's a disagreement between what Paul says and what Jesus says, Jesus wins. Period. Jesus was not hateful to those with different creeds than himself. That's the whole point of the parable of the Good Samaratan. He might have considered homosexuality to be a sin, it's really hard to say. Certainly the culture he grew up in did. Nevertheless, Jesus' ministry isn't about focusing on who is sinning and who isn't. Rather, it's focused on getting YOURSELF right with God. If you're worried too much about the sins of someone other than yourself or perhaps your children, you're starting to walk on thin ice. It's not always wrong to do this, but it often is. Further weakening this argument is that we cannot remove Paul from his 2000 year old chauvenist Mediterranean culture and say that somehow God prevented him from being influenced by his own culture. He says a number of questionable things, and many probably don't work in modern culture (things about women's dress and hair and other cultural anecdotes). Most of the other scriptural references to homosexuality are similarly of questionable merit (the Levitical holiness codes for example aren't considered binding to Christians). The sin of Sodom and Gomorrah is often brought up. The trouble is defining what in particular God was upset with. It seems that sexual immorality in general was the problem, and even if you consider homosexuality to be immoral, there are 1000s of other ways to abuse sex, so you have to do a mental check on yourself. Are you sure you're using the same level of concern for other sexual immoralities? Jesus for example said lust of the heart is equivalent to infidelity. That's a pretty high standard that most of us have trouble living up to.
Another Biblical argument against homosexuality goes: where were the first homosexuals then, in the Creation stories of Genesis? In other words, the theory goes, God didn't create us to be homosexual beings. He created two sexes, and this was done for a reason. Now this argument is a bit more difficult to dismiss, because even if you dispose of the Creation metaphors as simply stories, they are without a doubt stories with a purpose. They tell us "why" God created mankind, even if you don't choose to take them literally. The one weakness I can pick out here is that if you take that argument to its logical extreme, it would be sinful to send a man to the moon. God didn't intend for us to walk on the moon, but we've done it. So, did we sin?
One final Biblical argument against homosexuality deals with the moral effects of homosexuality. This argument is based on Jesus' answer to his disciples when questioned about how the disciples can distinguish those who preach His word faithfully from those who are false teachers or charlatans. His answer was: "You will know them by their fruit." In other words, you'll know by the results they achieve. When applied to those who consider homosexuality to be "ok", the focus becomes "Alright, what are the results of a homosexual lifestyle?" This is why so much debate goes on about whether homosexuals are truly happy, or whether they're living a kind of manic depression, and so on. It's also why so much focus is paid to the fringe cases of homosexuality where people clearly are hurting each other and are living completely immoral lives (in other aspects of their lives besides their sexual behavior). I personally am unconvinced by this argument, because I don't see enough evidence that homosexuality, separated from other immoralities, creates injustice and discord (like slavery did example).
So, there you have it. That's the main thrust of the debate from a Christian perspective.
Someone here posted that scripture has been corrupted and mistranslated, and therefore that's an argument for not trusting the homosexuality passages. Actually, that's an incredibly weak argument IMO. There are plenty of reasons to question the traditional Church stance on homosexuality, but that's not one of them. Take any other book of antiquity (Plato's "Republic", Virgil's "Aenid", Augustine's "City of God", Homer's "Illiad", Sophocles' "Antigone, and Philoctetes or Trachiniae", the "Corpus Aristotelicum", etc.) and you will find that the Bible, especially the New Testament has been translated with amazing fidelity throughout 2000+ years. Are there single point mistranslations? Of course, but usually those are corrected in a different translation, so the overall fidelity is preserved far more strongly than other books of antiquity. And why would we expect anything else? Those who copied and translated the Bible took the work very seriously, and would never have considered intentionally changing "the Word of God". Even if there were people with bad intentions, they would never have been the sole source of authority, and would have been "found out". That's why you should be wary of anyone who tells you to read only one translation of the Bible.
Someone else argued that the Bible's contents have been chosen by MEN, and therefore they're somehow illegitimate. Chauvinism has generally negative effects, and that's undeniable. We have to be careful making sweeping generalizations like that though. All thought leadership up until the 1800s was male dominated. That doesn't make it all worthless.
Anyway, great post all. I really enjoy these kinds of discussions.
--Cal