I also reported this earlier today on Slaw:
There was a rumour going around recently that the special Canada Post rate for mailing library books which some institutions enjoy would soon be discontinued. TALL President Wendy Reynolds has contacted the Canadian Library Association about it. She has confirmed this was just a rumour, that the book rate is continuing.
Moreover, Canada Post, the Canadian Library Association and l'Association pour la science et les techniques de la documentation (ASTED) launched a new tool for shipping library books with the Library Book Rate in late November 2005. Press release.
If you have any questions regarding the Library Book Rate or the Library Books Shipping Tool, contact the Canadian Library Association at firstname.lastname@example.org.