I know alot of people are afraid of an auction house - most important thing why is, they fear the lost of community that gathered or gather around a vendor house AND that vendors might go useless one day (because of an auction house WoW Style..) And i mostly agree to this BUT, you might (and with you i mean the Dev's
) consider the following option:
Chosen Cities will get an Auction house - WoW Style - you can easy implement it at the bank (kinda cool is the CASINO bank - might be usefull for that auction house option)
Vendorowners can go there and add their Vendor to the list - and mod it there too if they want (kinda like the vendor gump) - you can add yourselfe a vendor recall option, might even think about the house charg you to fill your recalls up (charge 20 gp for a recall scroll, or bring your own scrolls and drop them in (use a kind of "mark scroll in your pack" option, kinda like quest item mark) - you can even sort your vendor there maybe, and change prices on the menu (not have to be at the vendor to stock it) well might be a problem with vendor charges than (vendor penatly fees off?) - the auction house should NOT AT ALL be a external browser thingy, maybe ADD this some day as an app (why not) BUT charge for the app...
The main goal of ading a vendor search should be, people who are doing vendoring should have a new way to meet at this auction-house style thingy - you can discuss things their, meet friends ("Hey, were do we meet to go hunt? No worries, just meet at Monnglow Auction House!") have parties, etc...(wet t-shirt parties ftw)
In the end it should add more fun to the game and something new, than something to complain for - ya know...