A shot taken by the Lumia 928 was uploaded to Picasa by a Nokia employee (according to the associated Google+ account). What's interesting is that the photo was quickly pulled, but remains available thanks to @evleaks where the shot was published again. We're still attempting to create a collage with pieces of information on the Lumia 928, but evidence of the Windows Phone in action is certainly pleasing.
Taking a quick gander at the photo above, it's clear to see there's definitely quality present. MyNokiaBlog managed to save the Exif data (meta data for an image):
So what can we take from the shot and data? Well, it's of high quality, with good results in a well-lit environment (where the Lumia 920 still fails slightly in some regard) and according to the Exif data no flash was utilised so we can assume there's flash assist and OIS (Optical Image Stabilisation) on-board. We're looking at an f2.0 aperture, and a resolution of 1278x720, which could be limited by the automatic photo upload in Windows Phone (although the Lumia 920 will auto-upload at 1277 x 717)