A WPC forum user has posted many pictures of Black Lumia 925 running WP8 GDR2 OS update and Amber Firmware update. The pictures demo features like Sleeping screen (above picture), FM radio, Double tap to wake up, display color and saturation control, ISO up to 3200, Flip to silence, data sense and much more. Check some of the screenshots below and check the gallery at the bottom.
Last but not the least, Black Lumia 925 looks really gorgeous in real-life like all other Lumias than in press shots. That edge to edge display feel is amazing!!
Color/Saturation control:
Full Gallery:
Source: WPC forum