A wanted to buy board is interesting, but I think it has several issues and is not worth the effort:

From the perspective of the buyer, the main issue here would be browsing/filtering the 100,000+ possible items available to list the one you want to buy. We may be able to limit this somewhat with specific rarities (vanities, heroic, arcane, etc.), but there are probably plenty of items players would want to purchase that are outside of those parameters.

From the perspective of the seller, what player is going to continually review the list of items players want? Assuming they do find an item on this list, they'll more than likely balk at the price offered.

Use the forums, Luke!

-ALS