I would guess that they'll either liquidate the inventory in those stores or will simply ship it to the remaining stores. They might opt to do a combination of both. That said, if they liquidate inventory, realize that chances are they won't accept coupons, they won't participate in the rewards program, so you won't receive credit for your purchase, and they probably will not accept gift cards as a form of payment.
You can find a list of the stores they plan to close at
http://www.bordersreorganization.com...osure_List.pdf