I'm jumping in.
Before I give my perspective, let me share a few things I believe, so that there's no doubt:
1. Any and all sin is detestable in God's sight
2. Even one sin is enough to separate us from God (without Christ)
3. Breaking just one of God's given laws is the same as breaking all of them (cf. James 2)
4. Certain sins in Scripture are called abominations.
Now with that out of the way, here's my take on the apparent selective outrage by some Christians against homosexuality versus other types of sins:
It was mentioned upthread about how there seems to be a dissonance between protesting gay marriage and protesting divorce. It can be safely argued that we as Christians have been, in a sense, forced to accept divorce as normal and no big deal. It is so commonplace that we don't really express much public outrage against it. The difference with homosexuality is that one can be possibly charged with a hate crime and/or sued just for speaking out against it, either verbally or by actions. That is not the case with divorce really, or most other types of sin for that matter. People who are merely divorced cannot use existing anti-discrimination laws as leverage to get what they want or to justify their lifestyles. We don't have things such as "divorce pride" parades, promoting and celebrating divorced people as a way of showing "diversity" or "corporate responsibility" or similar things.
That's why there is a lot of pushback from the Christian community with regard to homosexuality. And it does often come across as selective outrage, to the near exclusion of other sins.
It is true that an unsaved person is just as condemned for lying only one time as he/she would be for being a practicing homosexual. It is also true that Christ is willing to forgive both types of sin if the offender truly wants Him to be his/her Savior.
That being said, although there might be others, I can't think of a sinful practice besides homosexuality that is being pushed down the throats of people so vehemently.
I'm sure that the early Christians spoke out against certain practices but were silent on others. Probably because they were put in positions where they were forced to accept or even participate in them under threat of some serious consequence, death in a lot of cases.
That's why I believe many Christians come across as being hypocritical with homosexuality as opposed to other sins.