Sorry if it's a repost, I looked and didn't see any. While I'm still waiting to buy the game itself as there's no cross buy between the Wii U and 3Ds versions, the soundtrack is available for free via the developers' website or name your price...
Free shipping although you will need to pay tax. $150 and includes Kinect Adventures (I confirmed with sales rep). You can also add more than one in the cart.
http://accessories.us.dell.com/sna/products/xbox_360/productdetail.aspx?c=us&l=en&s=dhs&cs=19&sku=a4049256