Specifications:

• 16.2 effective megapixel, full-frame sensor
• 10fps shooting with AF and AE, 11fps with focus and exposure locked, 24fps 2.5MP grabs
• 91,000 pixel sensor for metering, white balance, flash exposure, face detection and active d-lighting
• ISO Range 100-12,800 (extendable from 50 – 204,800)
• MultiCAM 3500FX Autofocus sensor works in lower light and with smaller apertures
• Two sub-selector joystick/buttons for shooting orientation
• 1080p30 HD video at up to 24Mbps with uncompressed video output
• New EN-EL18 battery (21.6Wh capacity, CIPA-rated at 2600 shots)
• Twin card slots – one Compact Flash and one XQD

See Shooting the D4! on Joe McNally’s blog and Thom Hogan’s article on the D4 introduction.