Updated with week 43!
The gap is around 2.5m in favor of The Legend of Zelda: Breath of the Wild!
There's only 10 more weeks to go before they're both 1 year old! I believe the gap should be over 3m at that point.
Bet with Teeqoz for 2 weeks of avatar and sig control that Super Mario Odyssey would ship more than 7m on its first 2 months. The game shipped 9.07m, so I won