Starbucks fans all over the country are rejoicing. Starbucks will begin serving its popular Pumpkin Spice Latte on Tuesday. This year Starbucks celebrates the 15th birthday of the drink that's become a big favorite. This year, Starbucks customers will be able to choose from more than a half-dozen PSL-flavored items, including Pumpkin Spice Cookie Straws and Pumpkin Spice flavored Ground Coffee K-Cup pods.