I was going to wait until I get all countries before posting, but it seems Papua New Guinea is never coming through so I'll just post now (a friend of mine who applied with same passport at the same time, strangely got Papua New Guinea as one of the first, but hasn't got others that I got, wonder what criteria these countries use...)
Here is my timeline:
Received mail with application confirmation and reference number.
Approved by HK immigration department according to online system.
Received confirmation letter and access to the APEC ABTC System.
Initial countries present in the list:
Hong Kong, China
Collected interim APEC card (I had requested China only as interim economy).
So waiting to see if Papua New Guinea ever shows up before getting final card, but no rush as I have the interim one now anyway (and hurray I can go to China now, perfect timing!)