Diamonds may not be a guy's best friend, but they certainly add elegance and status to his watch, as more men and watch retailers are learning. Indeed, one of the hottest niches in today's U.S. watch market is men's diamond watches—from moderate- to luxury-price ones—and it's getting hotter, say industry insiders and experts interviewed by JCK. "Men's diamond watches are becoming the new gold standard in style and prestige for men," says Gany Cohen, creative director for the Invicta Watch Group, echoing others. And these aren't only oversize diamond-pavé timepieces popular with celebrities. A growing number of more subtle designs with diamond accents, markers, and/or bezels are available in several categories at accessible prices from more brands. Rising Sales. Men's diamond watches aren't new; they've long been sales generators for some, such as Bulova Corp., which sells a subs