Given its surging quality, it can be easy to forget how young New Zealand is in the world of wine. The country's original winemaking pioneers are still setting the pace as their signature white, Sauvignon Blanc, becomes one of the fastest-growing categories in the United States. Kiwi Pinot Noir is also on the rise, offering fresh and distinctive wines that are easy on the wallet. Pinot exports have more than doubled in the past five years, and there's a sense among producers that the category is just revving up—and fine-tuning along the way. Wine Spectator's MaryAnn Worobiec explains.