Nikon Asia just posted this performance test video showing how much faster XQD memory cards are than the CF cards they’re designed to replace (400MB/s versus 160MB/s). On a Nikon D4S DSLR, the XQD could record 67 uncompressed 16.2MP NEF RAW photos at 11 frames per second (or over 200 JPEGs in a single burst).
The faster speed also greatly cuts down the time it takes to transfer your shots to your computer. In the test, it took Nikon 1 minute and 55 seconds to transfer 1000 photos from a CF card to a computer. Those same 1000 photos were transferred in just 35 seconds using an XQD card — a 3x improvement.