I wonder if May will be another month with PS4 over XBO by over 2:1 ... so far, the only month when PS4 sold more than double was in May 2014 (Watch_Dogs month and the pre-June pricedrop).
Many others months like January/April/September 2014, or the firsts 2 months of 2016 were close to that, but was still a bit under 2:1 gap.