First, sorry I posted a duplicate picture, y'all -- somehow Shasta's post slipped by me.
It would be great if the Obamas adopted from a shelter. The only problem might be that they apparently have to make sure the dog produces a minimum of dander and in a mixed breed, you can't always be sure what the genes will produce and according to his remark, they apparently intend to get a puppy.
A good compromise in that regard would be to seek out a runt or "pet quality" puppy from a breeder. These are animals with normal health and temperament but who don't conform enough to show standards for the breeder to use. That can be a rescue adoption too.