Recently many websites and blogs have been posting content on stockpiling for MoP. I wish to add my two cents to the conversation. At this time my stockpiling plan is very limited. The only item I am currently stockpiling for the expansion is Gold.
My reasoning for this is simple. This far in advance of release we do not possess enough information to make an informed decision. There is too little actual knowledge to guess. Even with limited beta access there is not enough data. The few details that we do know as fact may not even survive the beta changes to make it into the final release. While we can make generalized plans we do not have the hard data to begin making specific plans.
There may me multiple avenues that can make money in the expansion. One of these is the new pet battle system. However at this time I do not believe we have sufficient details to make an informed decision on which pets should be stockpiled and which will be a waste of time and gold. We need more specific information on current pet abilities and details on the new capture-able pets.
Another possible avenue for gold making is to make money off the leveling of new toons. This includes leveling of the characters and the leveling of their professions. Typically this would seem like an easy plan but recent changes made by Blizzard has me doubting the wisdom of this. One must consider that with the introduction of a new race we will have a large number of low level toons questing all at once. This will cause a huge sudden influx of materials being brought into the auction house at the same time. This includes cloth, ore, enchanting mats and items being dumped into the AH all within a short time frame. In addition we must take into consideration the new AoE looting ability, which makes farming low level areas easier, may have an additional impact on the availability of these mats.
An additional way to make gold off the expansion is to cater to players leveling their toons from 85 to 90. However we have not yet gained access to any information regarding the quests or crafting materials necessary at this time.
In conclusion, I believe that it is too soon to begin investing for the next expansion. We we see multiple beta releases followed by several releases on the PTR. There will be plenty of time between now and the final release of MoP. I recommend that everyone just concentrate on making as much gold as possible for now. One of the key attributes to a successful goblin is patience. However the most important one is knowledge. The first is found from within, the second from without.
Good Luck,
Jafo