I flew BNE-SYD this afternoon on VH-VBO and it was fitted with the new Y+ seats. I had allocated myself to 3C and in fact had the entire row to myself.
The seats are very comfortable - nicely contoured and the leather seems nicer than the regular seats. The pitch is quite good - I had plenty of knee space. There seems to be more space underneath the seats too because of their slimline design and what looked like slimmer legs.
All of the armrests are a little slimmer that the standard ones, and the middle armrests hinge differently (slightly forward of the chair back) obviously to enable them to move sideways when converted to Y+ format. I had a look but could not see how the conversion is activated/enabled. The L2A controls are in the side of the armrests (they are on top on the standard seats).
The tray tables are a little different to the standard ones, curved at the front and they slide towards you after being dropped. The Live2Air screen is the same size as the others although the moulding around it is a little different with the card reader a little more prominent (the moulding is recessed around it) and there seems to be more screen tiltability too.
All in all, I was quite impressed with the comfort of the new seats and the more spacious feel of the forward cabin. Premium economy will be a nice option for regular pax who are looking for a little more comfort.