Well... I always thought a "teddy bear" puppy is a Shih Tzu & Bishon Frise mix *designer mutt*.
Here's a pic:
http://www.puppyhavenkennel.com/imag...on_ShihTzu.jpg
I think a teddy bear Yorkie is maybe one that stays black & tan. Just a cutesy name for something that you can't guarantee - just like teacup.