Yeah, I guess you guys are right. It's been so long since I played MW2 that I had it in my mind that aiming was fixed at the torso, but now that I'm really thinking about it... okay, so other Mechwarrior games have done that. But that's okay, that just means (as Aenir said) that MWO is legit!
Valid point about the weapons, too. I seem to recall small lasers (maybe mediums) being the absolute uber-weapon in the Netmech Registry. But Piranha seems determined to properly balance everything, so hopefully that won't be an issue this time around.