If you have not sent your gift to the happy couple yet (I know how time just gets away from you. I MUST finish those notes to Vicky and Albert for inviting me to theirs) YES, books do make excellent wedding presents.
Used books can be passed off as family heirlooms. (You may have to explain that inscription to Bundle Bunny from Bunky-Boo.)
New books have nice sharp corners for throwing at reporters on the honeymoon.