As long as D3 has a good trading system these site will not be used for it. Everything is always about supply and demand. Because of that, I don't really know how gold and items will maintain value in the long run (Wow had a 1 up on this because they had the Bind on Equip function) considering items only tend to stack up over time.
They're already exploring an in game auction house system which (hoepfully) will be even better than the one they created in WOW. At this point I think it's just a bit of a waiting game to see what corrections they'll make to this problem so as to prevent the D3 system from falling into shambles.
The slanted eyes, so unearthly a gray color that they seized the attention of all who looked into them. Yet almost immediately those same eyes repelled, for in them Kentril sensed his own mortality.