A couple of days ago Metro Last Light developer 4A explained their reasons for not adding an option to change the FOV but promised a workaround.
An update has now been pushed live in Steam and the FOV can be tweaked in the .cfg file. Do remember that this may cause some display issues if you mess with it, the game interface was not designed to have the FOV changed but hopefully at some point in the future a more substantial update for this will appear.
A patch has been released on Steam to fix issues with AMD hardware, and improve performance for these cards. It’s live now, but might take a few minutes to reach everyone. Restart your client or verify local files if it doesn’t download automatically.
It also fixes a shadow visual corruption bug on AMD 7xxx cards, and fixes an issue with the game starting only in 3:1 resolution on some TVs.
In addition, you can now customize the FOV this way:
After starting the game up, the user.cfg will be updated with the r_base_fox attribute. You can find this in %LOCALAPPDATA%4A GamesMetro LL. Tweak it at your leisure!