These aren't anything fancy, yet. The main thing behind machineguns is that they freeze your movement for about one second so that you can't run around while firing. MGs will see more glory once I get in multiple ammunition types for them, like Armour Piercing.
Dual Pistols / Dual SMGs
This was the main 'beef' today -- which also consisted of realigning projectiles that are shot locally so that they appeared in the right places remotely (for multi-shot guns like shotguns or dual weapons) -- whereas you can now use dual pistols or dual SMGs to spew forth even more firepower. The balance to this is that the recoil-per-round is increased, the reload time is higher, and you cannot use active-utilities/tools (not implemented yet :P) while holding both. So hopefully with some tweaking they'll become nice and balanced.
(I'm always having so much fun while playing with my testers that I keep on forgetting to take screenshots. So, you keep on getting just boring old me. ;P)
This no longer should haunt me. For a long time now testers with lower-end systems had strange things occuring, like blood spewing out further when players died, or taking a longer time to come to a stop, or getting more recoil than everyone else. D'oh, I had forgot to apply the framerate-independance to the friction on particles/players. This was a little tricky because I was applying the delta value to the friction, which already tiny, so some precision issues arose. I still need to get this tested by the testing folks, but I'm pretty sure it's fixed up.
I love overkill. The concept actually originally came from a game I had written back in ~2001 where the player's corpse would be flung back with a trail of blood depending on how much damage you delt to him on his death. Therefore a shotgun blast at point-blank when your enemy has 5% health will send his corpse flying back, and a simple pistol shot from afar will only nudge him a little. Essentially only a visual goody, but (future) snipers and close-range folks will definitely get a kick out of this.
(Ewwww. Or is this a little too gory?)