After an almost two year long wait (these lenses where first announced in August 2010), Canon has finally set a shipment date for their new, and much anticipated, EF 500mm f/4L IS II USM and EF 600mm f/4L IS II USM supertelephoto lenses. A shipment date for the, in February 2011 announced, EF 200-400mm f/4L IS USM with built in 1.4x Extender has not yet been specified.
Expect hefty prices for these super lenses: the estimated retail prices are $10,499.00 and $12,999.00 respectively!
One of the reasons for the shipment delay certainly has been the earthquake and tsunami that struck Japan in March 2011. Apart from Canon most other manufacturers suffered production delays because of this too.