I've looked at a lot of Borders and B+N science sections. I have a book on the shelves in both stores in the science section - 6 years running now. (I wont say the Title though cause I'm shy).
But you are right about the ordering of the books. Sometimes it makes no sense the way they section things out. I did see mine right next to Hawking's once though and I thought - ah OK leave it there.
Stores near Universities will have bigger science sections.
Oh yes and Jeff is right B+N stocks what sells.