Video quality: optical stabilisation works
The outstanding light sensitivity for taking static photos is not applicable for recording video. Since the shutter speed is also limited for the Lumia 920 here (maximum of 1/30 of a second when recording at 30 fps), it doesn't score better in this department than the competition. It does have effective optical image stabilisation, as you can see below. The HTC 8X does not have any image stabilisation, and the iPhone 5 and Samsung Galaxy S III have software-based image stabilisation.
HTC 8X camera
With all this Pureview talk we almost forget the camera on the HTC 8X. And that would be a shame, since the HTC 8X alost has an excellent 8 megapixel camera. The picture quality is very good, comparable to the flagship models of Samsung and Apple, but its light sensitivity is not on the level of the Lumia 920. It's striking that the HTC 8X does increase the exposure time during video recording, which results in a sharp recording with good colour rendering and very little noise. It does have a lot of motion blurring, however.