Hardcore loyalists : a) would be expecting Gears to put in an appearance on Xb one well before the buying of it was announced; and b) never left Xb, or rather came back to Xb once MS did their DRM 180. These are the people who are buying the Xb one right now.
The Gears loyalists who were looking to move to PS4 because they thought it might go multiplat can probably be numbered in their 10's of thousands, not hundreds of thousands or millions, IMO. So sure, MS has brought these ones back, but it's not a big number in the grand scheme of things.
“The fundamental cause of the trouble is that in the modern world the stupid are cocksure while the intelligent are full of doubt.” - Bertrand Russell
"When the power of love overcomes the love of power, the world will know peace."
Jimi Hendrix
