Canon EOS-1D X specs:
100 to 51,200 native ISO (expandable to ISO 50-204,800)
30sec – 1/8000sec shutter speed
up to 14fps
3.2 LCD display
Gigabit LAN port
Dual DIGIC 5+ chips
Full HD 1080p video recording
The Canon EOS-1D Mark IV was announced back in October 2009 so this update is 24 months in the making.
Estimated retail price is around $6,800 (body only) and is expected to be released in March 2012.