Egads. "'Mormon' Church of Latter-Day Saints"? It's the The Church of Jesus Christ of Latter-day Saints.
It is interesting, but not so surprising, to find that "about 200" members of the church are leaving over the Proposition 8 issue. That's hardly a large number, though, compared to the more than 12 million worldwide membership of the church. There are always some who will find some reason to leave the church. That is their decision.
I do, however, take issue with your opinion that the leadership of the church injected itself inappropriately into a contemporary political issue. How was it inappropriate? Do church leaders not have the same freedom of speech as do any other person in the United States? Of course they do. They don't always exercise that right. Be aware that the church has consistently kept itself out of politics, the exception being when the political issues concern morals. It is then the right, and duty, of the church to speak out.