Canon USA has the Canon EOS M Mirrorless Camera Instruction Manual available for download (38.04 MB).
There is also a smaller Basic Instruction Manual available (8.42 MB).
Canon UK has the EOS M Camera manual available for download. Click the "Manuals" radio button for the download links to appear.
An updated Canon EOS 7D owner's manual is now available for download.
Updates are related to the upcoming Canon EOS 7D Firmware Uprade Version 2.0.X.
Canon has made the Canon EOS-1D X Owner's Manual available for download.
I don't track owner's manual page counts, but this might be a new record. (thanks Niklas)
Canon has posted a pair of in-demand PDF owner's manuals:
Canon Speedlite 600EX-RT/600EX Flash: owner's manual
Canon Speedlite Transmitter ST-E3-RT: owner's manual
For future reference, you will be able to find links to these manuals at the top of the Canon Speedlite 600EX-RT Flash Review and Canon Speedlite Transmitter ST-E3-RT Review pages. (thanks Niklas)
The Canon EOS 5D Mark III Owner's Manual is now available for download. (thanks Sean & Neuro)
Preorder your 5D III at B&H, Adorama or Amazon.com.
The owner's manual for the Canon PowerShot G1 X is now available for download.
B&H is listing the Canon PowerShot G1 X expected availability as Mar 5, 2012.
Links to Canon Lens Owner's Manuals in .PDF format are now included in most Canon Lens reviews. You will find the lens owner's manual link beside the first product image near the top of the page.