I don't know if anyone has really given this a look, but it is currently in closed beta on steam. It's not really a FPS but an Over-Shoulder view. The game is published by Square Enix and made by Psyonix. It pits humans vs vampires. I've enjoyed it for the little bit that I have played, and thought it would be worth a look. www.nosgoth.com
I've got 3 beta keys if anyone wants to try it out. It's fun and requires a lot of teamwork on both sides.