So far, that one week of unconfirmed XB1 "dominance" in the UK is looking more like a Pyrrhic victory, if it's even true.
Even a similar deal with Madden, the US equivalent of FIFA, couldn't push XB1 past the PS4. Call of Duty: AW and AssCreed Unity will also be on PS4 and everybody knows that, and FH and Sunset Overdrive are not system-sellers. Halo: MCCC will likely be a bump and little more at best.