The Guardian has the only positive review I saw.
The NYT has a negative review and calls it "a flagrantly old-fashioned, triple-hankie tear-jerker". New York Magazine says, "Autumn in New York is terrible". Empire Online gives it 1 out of 5 stars and concludes, "By the halfway mark you'll be desperate for Ryder to end her misery and yours."
BBC says it "proves unsettling thanks to the nauseating amount of glucose sentiment that infuses this predictable slice of doomed amour." Entertainment Weekly calls it "tastefully embarrassing". People opens a negative review with this: "They don’t make ’em like they used to, and Autumn in New York proves that maybe it’s time to stop trying."
Rotten Tomatoes has a critics score of 20%.