Amber update Firmware for Lumia 920 and 820 have leaked out indicating that actual update roll-out may be really near. The Amber update is supposed to bring many major camera improvements to older WP8 generation devices like Lumia 920 and 820 apart from FM Radio, Glance screen, SmartCam, Datasense etc.
The Firmware is available with flashing instructions at Windowsmania.pl. But may be you would like to wait if you don’t understand Polish :P.
Anyways, a video of a Lumia 820 flashed with Amber ROM is also posted demoing changes that Amber update brings.
In case you want to try it at your own risk, Flashing instructions.