The point is movement speed, Swiftness gives you early game speed to catch your target and give you late game speed to get across the map fast and so no target can get away.

Better buy berserkers greaves than boots of swiftness,You buy 2 phantom dancers? that will be a big movement speed

Standard but effective guide, I like what you have done with it so far. I would recommend looking at a bbcode guide to make your guide look more vibrant! get some pictures in there! Take a look at http://www.mobafire.com/league-of-legends/build/making-a-guide-101506 great guide that helped me!