The company calls this video card the "world's first GTX 670 for ITX/mATX gaming PCs," and after some research, it appears that they may be correct; most mATX cases will pretty easily fit larger cards, but ITX cases are certainly more limited (the noteworthy exception being SilverStone's SG08.
ASUS GTX 670 DCMOC-2GD5 Specs (Small Form Factor)
|GPU||NVIDIA GeForce GTX 670|
|Bus Interface||PCI-e 3.0 / 2.X|
|Video Memory||2GB GDDR5 @ 1502MHz
|GPU Clock||Boost Clock: 1006 MHz
GPU BCLK: 928MHz
|Resolution||2560-1600 DVI Max|
|Video Output||1xDVI-I; 1xDVI-D
|Software||ASUS GPU Tweak|
|ASUS Features||DirectCU Mini
|Dimensions||6.7" x 4.8" x 1.6"
In the marketing text, ASUS mentions that the chip has be pre-overclocked and uses a CoolTech fan with more efficient cooling technology to increase power and diminish thermals. The on-board heatsink uses vapor chambers (explained in our article) and a noise-conscious fan to help achieve a thermally-acceptable-yet-quiet cross. We haven't yet tested this 670, so I can't speak to whether it achieves the low noise threshold demanded by living room PCs, but the on-paper specs look promising.
Everything else is pretty standard for what you'd expect in a 670. The card will be available for purchase on 5/20/2013, roughly ten days from the rumored GTX 770 ship date.
This card was first announced back in April, but ASUS has finalized the ship date and price. The GTX 670 DCMOC will be on sale for $400 and is available for pre-order on Newegg.