Wine lovers looking for the next big thing are setting their sights on three grape-growing regions

You can tell who's hot in Hollywood by looking at the box office figures. You can tell what companies Wall Street favors by tracking the movements of the market. And you can get an idea of how many copies a book will sell by the number of times its author appears on Oprah. But how can you tell which wine regions are hot?

The world of wine, unlike those other worlds, has no single defining force, no reigning deity (though Robert M. Parker, Jr., comes close) to determine the ascendency of one grape-growing area over another. What exists instead is a more casual kind of consensus among restaurateurs, retailers, the winemakers themselves and, yes, the press as to which places are producing especially interesting and noteworthy wines.

I've been finding bottlings from the following three regions with increased regularity on the wine lists of some of the country's best restaurants, from Spago in Los Angeles to Le Bec-Fin in Philadelphia, The Wauwinet in Nantucket, Massachusetts, and Gramercy Tavern in New York City. They're also showing up on the shelves of some of the country's best wine shops, such as Sam's in Chicago and Zachys in Scarsdale, New York. And though the wines produced in each of these districts differ greatly, they all have one thing in common (besides the right raw materials): dynamic, ambitious winemakers committed to making wines of world-class quality and character.

Just when lovers of Spanish wines are learning to distinguish a Rioja from a Ribera del Duero, another first-class Spanish wine region that sounds like a dance done with hats has begun to emerge: Priorato.

An arid region about an hour southwest of Barcelona, Priorato is home to some of the biggest, most intensely flavored, most talked about and most modern red wines in Spain today. And the emphasis is most assuredly on the word modern. For although reds have been made in Priorato for centuries, it's only in the past decade or so that a handful of Priorato producers has become intent on creating wines whose stylistic models are more likely to be from France than from Spain. Indeed, certain Priorato wines have been said to be fashioned after such superstar Rhônes as La Landonne and La Turque.

The region's star winemaker, Alvaro Palacios, actually apprenticed at Château Pétrus, though his father owns a bodega in Rioja. Palacios makes his wines primarily from the native Garnacha grape, blended with Cabernet Sauvignon, Syrah and Merlot, and he ages them in new French barriques, one of many modern touches in this still largely traditional region. His wines are elegant if enormous, with a formidable structure and tannins so significant that even he admits that it takes 5 to 10 years of aging to soften them. He produces his flagship wine, the darkly brooding and immense L'Ermita, in minute quantities, and thanks to extravagant praise by the critics, it's virtually unobtainable. (When found, a bottle can easily cost upwards of $150.) Palacios does make a few slightly less exalted bottles, such as his Finca Dofí (about $50), that are worth a search.

Other prize Priorato reds, among them Clos Mogador, Clos Erasmus and Clos de l'Obac, are more approachable and a bit more affordable--about $35 to $60 a bottle. And given the Priorato producers' collective goal of making wines that rival the best in the world, they may in time prove quite a bargain.

Though the greater Auckland area has much in common with the Napa Valley in northern California--grapes, tourists and a big city nearby--unlike its Golden State counterpart, it's little known to non-natives. But it may be soon, owing to the international ascendency of such Auckland-based wineries as Kumeu River, Villa Maria, Selaks and Goldwater Estate. The region is also home to Kim Crawford, who has twice been named New Zealand's winemaker of the year, producing wines for both Coopers Creek and his own eponymous operation.

The greater Auckland area encompasses a wide range of appellations whose wines suit an American palate almost as much as their names--Matakana, Kumeu, Huapai, Waiheke--challenge an American ear. The region produces both reds and whites (though the grapes may be sourced from Marlborough or Hawke's Bay), but it's the whites--specifically Chardonnays and Sauvignon Blancs--that have won Auckland its widest acclaim. The best ones have a trademark intensity and a ripeness of flavor, as well as a palate-cleansing acidity, that make them particularly versatile food wines. The Chardonnays from Babich and Kumeu River nod to a California model (rich and full-bodied, often only very lightly aged in French oak). The Sauvignon Blancs from Goldwater Estate, Kim Crawford and Villa Maria look to the Loire Valley (steely, lean, crisp and racy).

Although there are notable Auckland reds, too, made from grapes as diverse as Cabernet Sauvignon, Mer-lot and Pinot Noir, few of these wines are available in the United States yet. But considering the praise the New Zealand press has already heaped on several of them, it may be only a matter of time before their reputation here starts to grow.

The white wines of the Menetou-Salon district in France's Loire Valley are sometimes called substitute Sancerres be-cause they are, by and large, several dollars cheaper than Sancerres. (They generally cost between $12 and $15.) I prefer to call them sybarite Sancerres for their richness and flavor.

Menetou-Salon is actually a geographic and a stylistic extension of Sancerre, its vineyards abutting those of the better-known appellation. In fact, the popularity of the region's wines has increased to such a degree that the area itself has expanded: today more than 850 acres are planted there, as opposed to the paltry 50 acres of 40 years ago.

Like Sancerres, Menetou-Salons are made from the Sauvignon Blanc grape, and they are similarly dry and crisp with herbaceous and mineral notes. A good Menetou-Salon has a more opulently floral nose than that of a Sancerre and a structure more akin to that of a Pouilly-Fumé. Like both of those wines, Menetou-Salon is best in its youth (it should be consumed within a year or two of its vintage). While red and rosé wines are also made in the region, they are harder to find and less likely to merit the effort.

Among Menetou-Salons, the wines of Château de Chatenoy are without peer. If you can't find them, those of two other producers--Georges Chavet et Fils and Henry Pellé--are worth seeking out. All three offer proof that this appellation is the source of some of the best wine values from the Loire Valley.