Canon made a surprise announcement today.
The Canon EF-200-400mm F4 L IS zoom with a built-in 1.4X TeleConverter.
The lens itself looks fairly compact despite the built-in 1.4x TC. What´s interesting is the ability to switch the TC on and off within an instant.
The lens is weather sealed and looks to follow the new sleek telephoto design first seen in the 800mm F5.6 L IS USM. If it´s anything near as good a performer as its prime sibling Canon users are definitely in for a treat.

Read all about it in the press-release HERE