Yes, they do pin trading at Aulani. When we were there in September 2012, it seems only the CMs who worked at the DVC Preview Center wore lanyards. But there are pin trading books available for you to look at at the General Store, the Concierge, and the Community Hall. I think there might be a pin trading book at Auntie's Beach House, too. Just ask the CMs and they will direct you to the right places.