What marital rights do out-of-state couples still lack in New York?

Estate taxes are one example. Typically, when a spouse dies, the surviving spouse does not incur estate taxes. But in New York, because of a statutory anomaly, a survivor spouse in a same-sex couple, who was legally married out of state, would have to pay estate taxes. These taxes can be significant. Also, I should note that even though many New Yorkers have gone across state lines to get married, many couples can't afford that.