The US government has confirmed that, because of the Holder letter, immigration cases involving married, same-sex, binational couples will be put on hold:
Following up on reports from this weekend, Metro Weekly just received confirmation from Christopher Bentley, the spokesman for the U.S. Citizenship and Immigration Services, that cases of foreign partners who are married to a same-sex partner and would otherwise be eligible for a green card are on hold in light of questions about the continued validity of the Defense of Marriage Act.
Bentley writes, "USCIS has issued guidance to the field asking that related cases be held in abeyance while awaiting final guidance related to distinct legal issues."
He notes, however, "USCIS has not implemented any change in policy and intends to follow the President's directive to continue enforcing the law."
The legal distinction means that although DOMA is still being enforced, the USCIS is using its discretion to hold off on denying green card applications where applicable.
That doesn't mean that they'll be granting green cards to everyone in this situation who applies and it's not really clear how that part of the decision will proceed. This is just confirmation that the deportation proceedings will be put on hold.