There is absolutely no reason to freak out over a 46 mana combo that rewards you with a 7/7 taunt, requires you to play cards in a specific order, to shuffle your win condition and to draw and play it manually.
It's a fun card, it will destroy bad decks and greedy bastards on expansion launch, and that's it.
I'm much more freaked out about the mage and warlock questlines, these are insanely easy to complete and the reward is incredible.
And yeah Celestial Druid messes with more game plans than you imagine.
It's not a 46 mana combo lol, you're just playing your deck - playing cards you'd play anyway when you'd want to play them. The ordering only has to be semi-specific. Also, it's a 1 card combo in the sense that you only have to fit 1 card into basically any control list. You don't have to waste hand space holding onto combo pieces or waste tempo tutoring/drawing for combo pieces, or waste more tempo setting up your combo (a 5 mana 7/7 taunt is not a waste of tempo). And yes, it obviously gets countered by celestial druid, but again, it only takes up one slot in your deck so you can easily build in multiple win conditions.
In a vacuum, this card is stupidly OP, but it will be completely wasted on a class that is worse than it's ever been since GvG in a completely aggro dominated meta. That's probably for the best though - if this was playable it would be horribly boring to play and horribly annoying to play against.