They probably have a button on them,like real grenades. If you hold done the metal bar on the side the grenade doesn't explode,it only explodes 3 - 5 seconds after you let go of the metal bar.
Sort of a bump but I want add my four cents. I don't think I'm going to have an emblem,they look sort f weird right there on the chest. Oh,yeah this is totally a bump.
I just started playing it,it's sweet you feel like your in a comic. The karma adds some fun to it,I'm starting out as a good guy,may go back and make a bad one. The cut scenes are animated,sort of in a graphic novel style. Not to far in,but as of now I think it's one of the best PS3 games I've played besides Uncharted. Holy crap,I started playing this at 10:00 PM it's 3:01 AM now.