In the US, the XOne could possibly outsell the PS4 with the release of Halo in 2015, but I don't think it will outsell the PS4 already this year. However, I could also imagine that the PS4 would be able to reclaim the lead during 2015 depending on the upcoming PS4 exclusives in that year. I'm pretty sure the sales numbers in the US will be close in the years to come.
BUT XOne outselling PS4 GLOBALLY?! For that they would need really strong sales numbers in Europe...certainly not gonna happen, not even with a 350€ SKU, hell not even a 300€ box would help that much! The boxes over here are en masse in traditional retail and online shops.
That "globally in the US" phrase is just... ^^