The black list array contains the number of days of the past 4 predictions, that helps solve redundancy issues, and tweeting the same prediction that has already been tweeted in the past 8 hours. 01 View Event #49 on Chart Cameron and Tyler Winklevoss released their own US based Bitcoin exchange dubbed "Gemini". After integrating Checkout for card payments, only one code change is needed to begin accepting Bitcoin payments—the addition of data-bitcoin="true" in the form’s code: