From the Starburst Facebook page "We just can't hold it in any longer. It's time to announce new Starburst Flavor Morph-with flavors that change as you chew! Check back here tomorrow for a chance to try them yourself!"
This message was posted on the website yesterday, so the giveaway should happen some time today. They have not specified a time. Hopefully it'll be some time this morning. Just "LIKE" Starburst on Facebook to get the latest updates on this possible freebie.