@yosuf3: Prices on auction could vary, say you got the fire place mount, i forgot the name, but lets use that as a example, now prices could vary on both sides between 100k gold - possibly 1m gold as i have seen some selling for 2.2m - 3.5m especially if it is the mount from the winter atoll event and so the same could be said for other items one could be cheaper on the opposite faction, it gives all a advantage in wanting to buy/sell.
@AOP: i kinda thought you could with Priden, but then you would have to go through the whole beginning part just to sell, plus they wouldn't know what someones after anyway if they are from different factions, i know they got selling characters upon both factions but this would add more items than what there is as both Auctions would be available to everyone, it would save them the idea of logging into their selling character, posting the item and jumping back to main, checking if the item is sold or not, turning the gold into crystals logging out to their main character and using the crystals for what they wish, to me and i think many others would agree that it is to much hassle, especially since now all they have to do is put the item up on auction, whoever on either faction needs it buys it and they turn it into blue crystals or purple even when the crystal exchange is at a low point for them, since also they would need to wait for a appropriate time to convert them as it fluctuates between 4800 - 5100 gold per crystal
The merged factions auction will allow everyone to buy/sell from any without hassle, both sides get access to more items and possible items one side has that the other might not have up say for example Imperial could have a Epic tear of the dragon and league doesn't, i being a league player would see the epic tears could buy it both players benefit from it.