After spending two decades as an undocumented immigrant, Venezuelan-born playwright Pablo Garcia (who overstayed his immigration status to be with his US-citizen husband Santiago Ortiz) has received his Green Card. The NY Daily News reports:

For most of their long relationship, Ortiz, 57, a retired school psychologist, was unable to sponsor Garcia — and being unable to leave the U.S. and return meant Garcia missed both of his parents’ funerals.
Their situation changed in June, when the Supreme Court struck down a federal law against gay marriage. Months later, some of the first same-sex New York City couples — including Garcia and Ortiz — have now been granted immigration benefits like permanent residency.

The article includes two other same-sex couples where one of the spouses has received a Green Card as a result of the DOMA repeal.

USCIS has a helpful Q&A regarding how the DOMA repeal applies to immigration cases. While the release states USCIS will work internally to identify and re-open cases (including the I-130 Petitions for Alien Relative, I-485 Adjustment of Status Applicants, and I-765 Employment Authorization Applications) denied solely based on DOMA section 3, it includes instructions for contacting USCIS to "alert" them of such cases. Importantly, the release notes: "For denials of I-130 petitions that occurred prior to February 23, 2011, you must notify USCIS by March 31, 2014, in order for USCIS to act on its own to reopen your I-130 petition."

USCIS also states regarding same-sex married couples who reside in a state where such a marriage is not recognized: "As a general matter, the law of the place where the marriage was celebrated determines whether the marriage is legally valid for immigration purposes...The domicile state’s laws and policies on same-sex marriages will not bear on whether USCIS will recognize a marriage as valid."