Heading up with the Halo. It's definitely heavier then what I'm used to.
The well designed helmet carry system. Black Diamond has standardized this through most of it's packs. It's a really excellent system that stows small and is easy to put on and take off. The toggles are a little small for bulky gloves, though.
Classic loop-style ice axe holder.
The hip belts are comfy and have a hidden pocket for the under leg strap shown here. This runs between your legs to ensure the pack doesn't get pulled off your body.
The avalanche pocket with Evac 7 shovel, BCA Snow Saw, and BD 240 centimeter probe.
The back hatch opened up with a daytrip's worth of gear spilling out.