It's the first good news Coke has had for some time in its battle to make up precious ground against PepsiCo Inc. in the beverage industry's most competitive rivalry. While Coke retains an iron grip on the $64 billion U.S. carbonated soft-drink market, it remains a distant second or worse in the up-and-coming "noncarb" category. Sales of beverages such as water, juice, tea, and sports drinks are growing as much as eight times faster than U.S. soda sales. Yet Coke's commanding 44%-to-32% lead over PepsiCo in U.S. soda sales compares with a 16%-to-24% deficit against its rival in the $27 billion noncarb market, says consultant Beverage Marketing Corp.