Very cool. I know that this was just playtime for the guys at Knight, but there are a lot of practical innovations that we are likely to see in future weapons. This could be quite practical with the addition of a heads-up display aiming system. Heck, I've got heads up display on my Acadia. I rarely look at the dash for anything. Heads-up helmets are already part of the soldiers arsenal and could easily become standard issue.
It does look like the SAW used in Aliens. Heavy on the cool factor.

Compact and full auto with a grenade launcher. Rock and Roll.