Yep, theres been a insider that said Fable, Avowed, Blade, Perfect Dark are comeing as well.
Ontop of that, you know stuff like Doom, and Elder Scrolls, Call of Duty, wont skip playstation.
So yeah... more games are comeing.
The "big three" ?
If they come, then everything might as well.
I think the xbox fans reaction to those games would be the worst, of all their games going other places.
So its likely something that MS atleast dont want to shout from the rooftops.
However, supposedly the new Gears is a Reboot, it goes back to before the 1st game, its a prequel, and afterwards they might remake the others.
If that happends, it makes sense to introduce the series to new customers on say playstation.
However I'm abit skeptical about about those 3 games, mainly because they are considered the "bred and butter" of xbox.