Are you up for a challenge? The folks at 7UP think you are. They've recently reinvented Diet 7Up to make it "more refreshing" and with "less diet aftertaste" and are wondering what you'll think. In order for you to taste it for yourself, they're sending out Taste Challenge Kits that contain the new Diet 7UP and two "competing diet lemon lime soft drinks." The kits are free, but the promotion ends May 20, or while supplies last. ...