[Zeitgeist]

That was from pwnage.tv which shut down for the time being due to a lack of corporate funding or some shit. They may come back according to a steam announcement though.
http://steamcommunity.com/groups/pwnagetv

pwnage.tv Robin Walker interview:
http://www.youtube.com/watch?v=sYd9wDY4Xac
http://www.youtube.com/watch?v=mNZAoIrEPpQ

in that second pwnage.tv clip, towards the end (around 4minutes 30seconds) the developer talks about Crit Mechanics, very interesting, as i had no idea they worked that way.

when you fire your weapon, it does a mathematical eqation and takes the sum of the damage you've done in the last 20 seconds and increases your chance to crit based on that damage, the ceiling is around 20%. so more damage = higher chance to crit.

thats REALLY interesting.

EDIT: grammer!