I think the videos are actually rendered ingame but put in videos. Probably so they could full AA and keep the framerate consistent.
played the demo on mates PS3 the other day - i enjoyed it; i tried to get him to get full game instead he got Dynasty Warriors Gundam
God of War had it first, and Gears can be know as GeoW in most places.
GoW has been used before God of War too.
It's inconvenient, but I don't mind it being used for either, it's quite clear which is used for which in 9/10 cases.
Gears of War is a bigger release than God of War anyway, so if it were to be used for either, it should be Gears.