What's in a grape name? Shiraz, once banned from French wine labels to avoid confusion with its Rhône Valley namesake syrah, has made a triumphant return as the marketing name of choice everywhere from the South of France to Franschhoek. California's successful promotion of its own zinfandel has added such value to the grape variety that southern Italian producers have successfully lobbied to use the name on their labels instead of its Italian namesake, primitivo. Conversely, merlot's status as the "red chardonnay" has been undermined by the more glamorous pinot noir grape, due in part, no doubt, to its starring role in Alexander Payne's hit film Sideways.

What's hot is hot and what's not is not. Take chardonnay, a grape so popular that it became the choice of a million Bridget Joneses and spawned a fictional footballer's wife. Where once chardonnay was a synonym for wet, white and wine, now pinot grigio has become the latest shorthand for another bland and vacuous style of dry white - the preferred form of medication for Bree van de Kamp, the supermum from Desperate Housewives.

Pinot grigio appears to be threatening chardonnay's position as the dry white brand of choice with not just Italy, but California, Australia, Argentina, Hungary, Germany, Moldova and even France among nations now dumping its French namesake - pinot gris - in favour of the more fulsome-sounding Italian version. Even Germany's Blue Nun has flashed an ankle with the launch of its own pinot grigio. Pinot grigio may be a synonym for the tokay pinot gris of Alsace, yet only producers in Oregon and New Zealand have held out and stayed faithful to the original classification of pinot gris, using it on their labels. And it's no coincidence that these two producers are the most authentic purveyors of the true, full-bodied Alsace style.

To be fair, pinot grigio is so imitated because it is capable of such good things. Like the 2004 Pinot Grigio, Lis Neris, £11.95, or £10.75 bottle / case, Berry Bros & Rudd (0870 900 4300), a stylish dry white from Friuli containing the juicy fresh pear and peach fruitiness and zingy freshness of the best of pinot grigio. In the face of anonymity, the refreshing fruit and grapefruity twist of the 2005 Da Luca Pinot Grigio, £4.99, Waitrose, is a cut above the average brand, while the invigorating zip and zing of the 2005 Sainsbury's Taste The Difference Pinot Grigio, £7.49, a cut and a half above average. The problem arises when the volume of imitators exceeds the limited number of superior examples. According to the Italian specialist Nick Belfrage MW, "there's too much phoney stuff around calling itself pinot grigio".

One company that seems to have fallen under the spell of pinot grigio is Marks & Spencer, whose spring tasting guide extols the virtues of "the sexy and magical words Pinot Grigio". At the M&S summer tasting, pinot gris - whether from Alsace or Germany - was re-branded pinot grigio. I could take or leave the Alsace pinot grigio, but I was impressed by the German example, the 2005 Palataia Pinot Grigio, £6.49, an excellent, well-crafted dry white with opulent, peachy fruit richness and citrus-crisp acidity. M&S are getting their Italians right too. Both the lively apple and pear fruitiness of the 2005 Friuli Pinot Grigio, £6.99, and the zingy, full-flavoured richness of the 2005 La Prendina Alto Mincio Pinot Grigio, £7.49, showed that pinot grigio doesn't have to be confined to the desperate housewives of this world.