Wow. A vanilla curved Windfury minion.
Although I think 2/3s are better than 3/2s in constructed and prefer 3/2 abilities that affect board instead of face (like Knife Juggler) on its good days, I think you have to jump on the hype train for the 3/2 windfury guy for sure. Shieldbearer already fits and works rather well in a Shaman deck, and with this six damage swing potential here I think shamans will have little issue justifying Shieldbearer's inclusion to protect Whirler (shall we call it Whirler or Zappo?).
Zoo will get the biggest middle finger from Whirler and I love it. A Shieldbearer - Whirler opening will be hard to get through with minions and Soulfire is the only removal that ignores taunt, and it's a bit "over costed" for removing Whirler. Meanwhile the six damage is most relevant against Warlocks because they tap so much, and Shaman has some direct burn to finish the job. (It'd rarely be only six, you run flametongue, probably Dwolf alpha, and rockbiter in this kind of deck. Let alone the mech buffs).
Most of the other classes have spot removal to deal with a taunt-whirler opening, and most of the other classes have AoE later on to punish you for putting a 3/2 without immediate effects in your deck, so I think it will be balanced and not break the game.