Falling in Love is a polite little romance, the ambition and appeal of which are modestly slight. Dynamic starring duo of Robert De Niro and Meryl Streep keeps the film afloat most of the time.Both De Niro, a construction engineer, and Streep, a graphic-designer, have marriages which, while not unhappy, have settled into the routine. Meeting in Manhattan and on the commuter train to and from Westchester County, they are compelled to continue seeing one another, but are unsure where it’s all headed. More quickly than Streep, De Niro decides he wants to have an affair, but she can’t make up her mind. De Niro is charming and, like Streep, plenty of fun to watch, but he is very contained here compared to his usual work.