Shurikenjutsu is cool, but the damage is quite superficial. A bullet can kill you, but I've never heard of a throwing knife being able to kill someone. Well, unless you threw a big honkin' bowie knife.
But, what Kaimetsu said was accurate. The average time necessary to take a gun out of a holster is much longer than the amount of time necessary to grab a knife- depending upon where you keep them. I've had a few friends who were into knives (I never was myself), and they liked to keep them on the shins. You could see that it would take a while to fetch a knife down there. But, with a nice strap around the forearm holding some shuriken darts, you could throw a dart before a policeman could could budge his 9mm. Still, if you threw it at the policeman, there's no way you'd be alive in the end. A dart can't kill him.
A sword, on the other hand... I read a weapons study once, done by a fellow who was both a practicing student of iaido and a former member of some military branch... can't remember now, but, anyway: he timed his draw for several types of guns in holsters and a sword, and, surprisingly, the sword was number one in all cases. The thing is, of course, the sword only had that time within a range of 6 feet.
But, if you hit someone with a fast iaido draw, it's sure to kill them. If you think about it, the faster a sword draw is, the more effective it is, while the faster a gun draw and shot is, the less effective it is. And, a bullet wound is comparatively insignificant to a strong cut.
Finally, a sword can stab, and sometimes cut, through a bulletproof vest. But, at 6 feet, you're average bullet can also.
