If you've been playing Hearthstone since the Gnomes vs. Goblins expansion, then you should remember a card named Jeeves. It had a very similar effect, but Voracious Reader is much better: it only draws extra cards for you.
Since it's a rather cheap card and it's neutral, many tempo and aggro decks will want to have both copies of it.
Face Hunter players will be especially happy to get this, as card draw is the weakest point of these types of lists. Not anymore!