I didn't notice any torso twist in Hawken. That and the footage worries me a bit. Like someone said it looked like a regular twitch shooter but with mechs. As a former Quake/UT player I like twitch shooter but I love Mech games just as much.
I used to enjoy going toe to toe against a Daishi with my Mauler. The abitlity to twist the torso gave me the option to sacrifice my back armor and specific torso or arm weapon to survive long enough and get the kill. Well that along with movement of course. In other words, I could also use the twist to distribute the damage.