I have been on a 5 year break from World of Warcraft. This gives me the ability to see what the changes have been; and, if these represent a logical growth in the game. I'm sorry to say that key in frastructures in the WOW world have not been adjusted as each new release is downloaded. Prime example, and probably the most important to the WOW economy has been the total lack of restructuring the Auction Houses. The prices are ridiculous and meaningless. The AH are nearly empty; where once they were crowded with players trying to work the market. Buying reagents and materials for you profession is impossible. I see special items being sold for thousands of gold. Kobol candles are even being sold in the AH.
Blizzard needs to restructure the AH economy to address all levels. Auction Houses in higher level areas should only allow items that fall within the levels of that region. This type of segregation is reflected in our own society. Some people shop at Walmart; while others shop at Christian Dior. These two groups do not intermingle and have much different needs.
If the AH situation is not addressed by Blizzard they will see a lack of "new" players joining and many old hands leaving in frustration. If Blizzard doesn't know where to start, I suggest the AH. It will have the advantage of getting the economy kick started.