Perfect yes, the Orca is what I used. Thank you, it's been bugging me. I looked at it earlier on the site but I didn't think that was the one. Thank you.
They were using Razer Onza (I think) controllers on the Most Wanted booth. They were quite nice, with low travel buttons and a good d-pad for menus (though I reckon it'd be pretty useless for fighters).
Headset-wise I noticed they were using Razer Orca's on the Horizon demo, notable for their lime green headband. Not sure what they were using on the Halo demo, as I didn't bother with that.