To be honest, I could see this being played in aggro decks to refuel on 7, kind of like a balanced Divine Favor. Other than that, it's kind of interesting, but not something that's an auto include for sure.
This only works in an aggressive deck vs any slower deck. But then again, most slower decks have lots of removal and attrition cards - which card aggro doesn't need. Not necessarily a horrible card, but just too bad to be good in any kind of deck as of now.
Imagine including this in an aggro deck. It's a dead draw against aggro mirror, but against control, it's basically "Battlecry: draw a bunch of high-value cards from your opponent's deck". A great little tool, but I doubt it's quite worth it.
I think in Aggro it's the neutral hand refill card for all classes. By turn 7 you've just seen your opponent play his 3rd board clear, now you have 1 card in your hand and he has around 6-7. Play this and you can now have some mid game or something to work on finishing.
And yes if you're vs control you'll get high value cards, but you just spent 7 mana on a 3/3, your opponent has the benefit of the first move, and his deck has better synergy with the cards you now have in hand.
But what is better? - Spending 7 mana on a 3/3 and drawing gas? - Spending spending less mana on something low impact and continuing to top deck?
It really depends on how aggressive the decks will turn out to be and logically how the meta as well. If you ask me this card has some potential - extremely bad (and slow) against aggro and aggro-ish mid-range decks, average versus control, but really good against value decks. Against combo - well, it's about the information about your opponent's hand and sometimes you would like to to throw away dead cards like AoEs for more burn (e.g. against freeze mage).
So dunno. I think this fits a casual deck better, but I like her potential. Niche card and nothing more.