Replaced 'Sharp' falloff with 'Soft'. This falloff type has a variable softness, and can get some quite smooth results. It can be useful to get smooth transitions in density when you're using particles on a large scale: http://mke3.net/blender/devel/rendering/volumetrics/pd_falloff_soft.jpg Also removed 'angular velocity' turbulence source - it wasn't doing anything useful atm