As most folks have already stated, the 58 is basically a 57 with a ball windscreen added. The ball was basically added for live vocal use where a pop-screen is inconvenient. With good mic technique the 57 will work fine for this as well but the 58 is a little better with sibilance than the 57 in everyday live use.
Some will argue with this, but I can't hear the difference between a 57 and a 58 with the ball removed.