I like this line from the pitch video:
Any time I laugh, or when people are playtesting it, if they laugh at something ridiculous, even if it's a physics glitch where a helicopter flips upside down and chops you in half, that I never even intended to happen, I'm leaving that stuff in.
Yes, this sounds like the kind of person I want making my videogames.
The game is being developed by Jason Stokes, a former environment artist at ArenaNet on Guild Wars and Guild Wars 2. He's been working on Bullet Bros for a year now, and the footage from the Kickstarter pitch video suggests he's made some decent progress. Now he's looking for funding so he can hire help. Mainly, that'll be a programmer who can write better physics and networking code, but he outlines other plans on the page itself.
Watching the video and looking at the screenshots, it reminds me of Intrusion 2, last year's criminally overlooked and similarly co-op, physics-enabled Contralike. That one had a helicopter with muscly arms in it, which it would use to crush you and then pump in the air in victory.
More Bullet Bros screenshots: