The successors of EF 800mm f/5.6L IS USM, the Canon EF 800mm f/5.6L IS II lens to be announced in 2013. The replacement for the EF 800mm f/5.6L IS expected to be announced after the release of the long awaited EF 200-400mm f/4L IS 1.4X lens in the second half of 2013.
Along with the EF 100-400mm f/4-5.6L IS II lens announcement expected this summer, after the EF 200-400mm f/4L IS 1.4x lens become available in stock and shipping, Canon is also planning to publish their super telephoto lens.
Canon EF 800mm f/5.6L IS II Lens to be Announced in 2013
Canon sure be thinking to take the advantage of the lighter weight technology and produce their Series II model with a serious weight reduction. Rumored EF 800mm f/5.6L IS IIs may also have built-in teleconverter.