The vote-counting isn't quite finished yet, but it's clear that gay marriage in the Republic of Ireland has won resoundingly, with yes votes ranging from 50% in some rural areas to almost 80% in parts of Dublin. Ireland thus becomes the first country in the world to approve gay marriage by referendum.
To anyone familiar with the country's cultural history, this is astounding. Barely a generation ago, Ireland lay under the absolute domination of the Catholic Church. Contraception and divorce were illegal. Homosexuality was not decriminalized until 1993 (though note that even that was ten years before Lawrence v. Texas achieved the same in the last dozen states of the US). The Church led the "no" campaign in the marriage referendum.
But every political party, and most other major social institutions, openly supported "yes". The Church's millennium-old grip upon Irish culture and thought has been swept away in two or three decades. And Ireland isn't alone. Gay marriage is already legal in other former bastions of Catholicism such as Spain, Portugal, and Brazil, and other forms of social progress have made similar headway against the Church's opposition -- contraception and divorce, for example, are not only legal in Ireland but already fairly uncontroversial.