I did YVR->SYD (and back) with my wife. On the way there we did as the aeroplan agent suggested and sat one behind the other in a window seat. It was difficult to communicate in this position. On the way back when we checked in we chose to move to the middle seats side by side. There is a little center wall you can open (not much, but it helps) which then allows you to communicate more freely without shouting across the aisles. In the two middle seats when slightly reclined it is pretty easy and painless to communicate. When we fly this configuration again we will choose the middle seats.