Here is my Thread you are referring to :
http://www.onethumbmobile.com/celticher ... ent#p84098
But Deathbytray, My suggestion is for the already-designed auction house/trade hall to be located in The Settlements.
I think your idea is excellent, to integrate the post office and auction house so a player would check their post office account (and if they haven't yet been to the trade hall that day - even though they may be next to each other) they would see an administrative message saying if they are still the highest bidder on an item, or have been outbid).
My idea for The Settlements is to integrate many of the non-combat activities into one serene and beautiful zone. We would have player housing there (much of the player housing would be instanced for people who can only afford a slight purchase cost and maintenance fee). It would look like an apartment building (in CH aesthetic of course!) but when you click to enter it, you would see your particular room. For those who can complete the quest and have more money, they can get a physical house with a sign out front and all that goodness. People can visit and see how you have decorated. And there will also be clan halls available for even more cost where many people can have a physical room inside for decorating and banking. Think like upstairs Tavern but with a purpose! Anyhow, check that thread for more details.
Thanks for referencing me Deathbytray. I think it sounds good to integrate the mail service and the trade hall. Though, for the record, I am not in favor of trading between servers. I do not think the developers would be either. It is hard enough for them to balance each individual server and the drop frequency formulae. and the ability to do that goes out the window when we can now shop drops from other servers. I think internal trading is fine.
