More Canon lenses coming in 2013. From the trusted source, the successors of Canon EF 800mm f/5.6L IS USM and EF 100-400mm f/4.5-5.6L IS USM are to be announced late this year.
Canon EF 800mm f/5.6L IS II USM lens:
This lens is rumored to be announced once the EF 200-400mm f/4L IS 1.4x lens is in stock and shipping. The announcement would be sometime in fall, 2013. Also rumor this new 800mm lens may has built-in teleconverter.
Canon EF 100-400mm f/4.5-5.6L IS II USM lens:
This lens would probably announced in late August, 2013. Some prototypes of the lens are currently in use in Asia. The main reason for this quick update is Nikon has released the new 80-400mm lens.
via: CR
juste comme sa le 100-400mm serais plus gagnient si il etais pas pompeux
Hope the 100-400 II does not have a push pull zoom action like the current lens. Main reason why I never bought the current one.