Unlike the keyboard, which could be installed on any device, this camera app rip is only available for the Galaxy Nexus, and obviously it must be rooted. The update is a ZIP file, which can be flashed via ClockworkMod Recovery. Remember, if you flash the ZIP, it will replace the stock app, so it's a good idea to make backups before flashing.
The backup may be more necessary with this one than the keyboard, because while we had no issues with the keyboard, the camera hasn't worked for us yet and force closes when we try to open it. Others have had success with it, but so far, we're not so lucky. So, if you want to play around with the new PhotoSphere option in the new camera app, proceed with caution.