Those of us using the PIXMA Pro9000/9500... This driver was just released and is later than the latest Canon drivers from their Website (I wish there'd be a single source for these). Here's the link for the direct download:
http://www.apple.com …s/canonprintdriver11.html
It's a 267MB download for Mac OS X 10.5.3 or later. This is the most recent update to Leopard, so there is no "or later" right now. 
Caution to those updating from 10.5.2 to 10.5.3 anyway - there are some rather serious bugs with Adobe CS3 which includes possible file corruption when saving to a remote volume!
