A lot of people seem to be making the assumption that because Eich, or any other person, supported measures such as Proposition 8, they are hateful, or bigoted, or support the restriction of the rights of the LGBT community. While I'm sure there are those supporters that do, this view often doesn't apply to a majority of these people. In this case, the rights that concern many members of the LGBT community with regards to gay marriage have to do with a gay couple getting the benefits that a straight couple would, as well as the freedom to not be persecuted for their union. For the most part, there is no problem with this among the opposition.
While the benefits associated with marriage were originally put in place to ease the challenges of raising a family, financial or otherwise, there's no reason why a gay couple couldn't raise a family of their own through adoption/surrogacy/etc. As such, these benefits should certainly apply to them. Likewise, a straight couple may get married, but have no children, meaning the benefits are probably of less need, but are still given. So for the most part, people opposing gay marriage aren't necessarily doing so to restrict the benefits a gay couple would receive. And with regards to the freedom from persecution for a gay couple, there is even less reason to oppose it.
More often than not, the focus of the opposition often boils down to the spiritual concept of marriage. This has less to do with the rights and freedom of gay couples, and more to do with the preservation of marriage as a spiritual concept. You can bet that if it were only a question of the government administering the rights and benefits of a civil union to a gay couple, there would be a lot less of a furor from those that oppose gay marriage.
As such, it's fairly presumptuous to assume that those who are against gay marriage are against the rights of gay couples. Sure, there are those who walk around with signs saying "God Hates Fags," but they certainly don't represent the majority. As such, vilifying those who supported such measures as Prop 8 comes across as hypocritical, especially from a community that has had to endure similar persecutions for such a long time. (It's reminiscent of how after WWII, Germans across Europe were thrown in concentration camps as revenge for the actions of the Nazis during the Holocaust.)
So this whole reaction to Brendan Eich is pretty disappointing to me, since it was his own, personal money that he contributed, and especially since he has stated he won't let his personal viewpoints affect Mozilla. As another Slashdotter pointed out above, if you boycotted all the companies lead by those whose personal opinions you disagreed with, you might as well become a hermit.
Also, bite me, OKCupid. I'll use whatever internet browser I want to use. You know what I won't use? Your website.