The Proposition 8 case from California, on these questions: whether the 14th Amendment bars California from defining marriage in a traditional way, and whether the backers of Prop 8 have standing in the case under Art. III.
The Windsor DOMA case is granted on these questions: whether Sec. 3 of DOMA violates equal protection under the 5th Amendment; does the fact that government agreed with the 2d Circuit decision deprive the Court of jurisdiction to hear and decide the case; and whether the House GOP leaders who brought the case have Art. III standing in this case.
The standing questions in both instances leave the door open for the Court not to decide the cases on the substantive issues should it find that the parties who brought the cases should not have.