Quick information on how it all works.
Subscriptions: Subscriptions are only available to registered DiabloHub users and allows them to be notified when a item they are subscribed to goes above or below a certain price. Users can choose to be sent an email or simply have a website notification sent for the items they subscribe to.
Favorites: DiabloHub users can favorite an item and have it pinned on their own personal favorite category, where you can easily track all your items.
Graphs: Graphs are available for every item. Various time ranges are available for more detailed information.
Commodities: The current displayed price of a commodity represents the average trading price of the item since the last price update.
We track average sold price rather than listed price to give a more accurate representation of the items actual value. Because of this the listed price of items may differ from the values found ingame. For example it is quite common for a player to post a Legendary Plan for $200+ when no other plans of that type exist. However since the average trading price of that plan is actually $20 it does not benefit anyone to track the $250 value as it is not sold price and only serves to mislead people.
Item Tracking (Armor, Weapons, Etc): Currently only commodity tracking is available. We are trying to figure out the best way to track prices of items, which is rather difficult due to the random nature of item stats. If you have any suggestions please post them in the forums.
Price Tracking began on July 10th, 2012.