Gay Marriage: South America

Argentina:
After 14 hours of debate in mid-July, the Argentinian Senate voted 33 to 27 to approve La Ley de Matrimonio Igualitario (the Equal Marriage Law), making Argentina the first Latin American country to grant same-sex couples the right to marry and the critically important benefits that accompany the union. Argentina has established an elite status as one of 10 countries with legal same-sex marriage and a progressive leader in South America.

Brazil:

The recognition of same-sex unions in Brazil have occurred since 2004. But now, same-sex couples have more rights. Now they can adopt children, they have rights to pension, inheritance tax, social security, health benefits, joint property immigration, IVF as well as surrogacy. In 2011, the Brazilian Supreme Court ruled that same-sex couples are legally entitled to civil unions. Although same-sex marriages are not legally recognized, same-sex couples are able to convert civil unions into a full marriage by pleading a case to the Supreme Court.
Below are cities in Brazil who have accepted to convert civil unions into full marriages:

June 27, 2011: City of Jacarei convert a gay civil union into a full marriage.
June 28, 2011: City of Brasilia convert a lesbian civil union into a full marriage.
July 7, 2011: City of São Bernardo do Campo convert a lesbian civil union into a full marriage.
July 29, 2011: City of Cajamar convert a gay civil union into a full marriage.
August 3, 2011: City of Recife convert a gay civil union into a full marriage.
August 24, 2011: City of Rio de Janeiro convert a gay civil union into a full marriage.
September 13, 2011: City of Soledade convert a lesbian civil union into a full marriage.
September 17, 2011: City of Jardinópolis convert a lesbian civil union into a full marriage.

Chile:

Chile does not recognize same-sex marriages. The president voiced her opinion in support of civil unions but the Catholic church as well as several members of congress were opposed. In October 2009, a civil union bill was introduced but failed to pass. A debate in favor of civil unions is ongoing.

Ecuador:

Civil unions were legalized by the approval of the 2008 Constitution of Ecuador and was implemented in 2009. Same-sex marriages are constitutionally banned in Ecuador, although same-sex sexual activity is legal.

Same-sex couples and households headed by same-sex couples are not eligible for the same legal protections available to opposite-sex married couples.

Mexico:

Mexico's Supreme Court has upheld a landmark law permitting same-sex marriages in Mexico City, rejecting the conservative federal government's claim that the law is unconstitutional because it threatens the institution of the family. Click for more info

Same-sex couples in Mexico's capital today can marry and adopt children.
Click for more info

Same-sex marriage is legal in Mexico City —the Federal District of Mexico— having been approved by its Legislative Assembly on December 21, 2009 and signed into law by Head of Government Marcelo Ebrard on December 29, 2009.The law was effective on March 4, 2010.
Civil unions, known as Sociedades de Convivencia and offering some of the rights of marriage, have been legal in the city since November 2006.