Back on January 6, Nikon had pre-announced the development of the D4S, but they provided few details: http://www.photo.net/nikon-camera-forum/00cI3u The general description Nikon provided at that time sounds like some rather moderate improvements, as it is typical for S type updates. To me, the surprises are: The price has gone further up by $500 to $6499.95. The official announcement comes one day after the end of the Sochi Winter Olympics, instead of a few months before a major international sports event. However, I am sure that a number of sports photographers used pre-production versions at Sochi. It turns out that the D4S has quite a few improvements, although most of them are fairly minor, nice-to-have type enhancements. Here are some of the highlights: The D4S remains to be 16MP with a 4928×3280 RAW image, but Nikon has updated the sensor so that its ISO range is extended to ISO 25600 on the high end, one stop higher than the D4. The processor is updated to the EXPEED 4, as the D3300 and D5300. According to Nikon, the processing power is 30% faster, such that the D4S can shoot at 11 fps, up from 10 fps for the D4. RAW Size S: small size RAW: 2464×1640 or about 4MP Auto Focus: still the Multi-CAM 3500 with 15 cross-type AF points, but there are some new AF modes, such as Group Area AF that uses one main AF point and its four adjacent AF points to track moving subjects. The rear LCD has adjustable colors. New EN-EL18a batter with higher capacity but still interchangeable with the original EN-EL18. Memory cards: still 1 XQD + 1 CF The D4S can capture 1080/60p video and deliver it uncompressed from its HDMI output. It can write video files onto both memory cards simultaneously in the backup mode. Nikon expects to start shipping the D4S on March 6, 2014. The FIFA World Cup (football/soccer) starts in June, so it is still over three months away. You can find photo.net's preview article here: http://www.photo.net/reviews/nikon-d4s-preview/ Nikon D4S with the 58mm/f1.4 AF-S Lens, news image copyright Nikon Inc.