Actually, no...it's 10 bit/channel to the print head for the Canons...not 16 bit. It takes a 16 bit image and 10 bits of precision...not 16 bit. And, besides, Photoshop's 16 bit is actually 15 bits + 1 level.
Well Mr. Schewe, if we are being picky, it's actually 12 bit for the Canon Plug in according to Scott Martin from Onsite who writes, "I have confirmation from Canon NY that the plug-in's 16bit option is really 12bits".
Or is it actually 10 bits + 2 levels?
The point I was trying to make, is that there are ways of printing more than 8 bit from Photoshop without having to invest in a RIP. Granted it would be great if Adobe would develop an option to print either 8 or 16 bit from their print dialog. With the capability of 16 bit printing from Leopard and some ink jet printers, Adobe is the weak link in the chain right now.