I did a search and found these two images in particular that caught my attention:
http://i583.photobucket.com/albums/s...pse15b8c51.jpg http://i583.photobucket.com/albums/s...psb58c10d8.jpg
(In this image, the dog on the right is the biewer/yorkie mix)
In my humble (and inexperienced) opinion yorkies and biewers
look exactly the same exept for their colour (both are gorgeous), so the resulting pups will look exactly like a yorkie/biewer..the only surprise will be the colour of their coats

I know this mix will be frowned upon..in the US, breeding in general seems to be one of gods great sins there lol, but I don´t think the owner will have any trouble placing those pups in good homes, neither does she have to worry about them growing up, weighing 25lbs and looking like bloodhounds

The outcome is going to be pretty predictable when it comes to looks and size and no doubt, they´ll be adorable.
Is she a breeder? (asking because she has an intact male and two intact females).I´m asuming that being from the US, and in the case that she
is a breeder, both her females and her male are all healthy (tested etc) and well looked after?
If so, now that this is done, I just hope all goes well and that momma has a safe whelping.