Must, must, must set the record straight on this one. I was taught by sommelier Johnnie Walker (real name, fabulous person) in Glasgow that a Kir Royal is made with Champagne and the tiniest dash of creme de cassis (made from blackcurrants). It's supposed to be "salmon" pink, not scarlet. Some people use liberal amounts because that's how they like it to taste, and some people use Chambord instead. That's made from raspberries, so that flavor profile is very different too. Either way, enjoy it. People often forget about Champagne. We really shouldn't.