Speaking of ore, Blizzard has changed the number of nodes of a variety of types of farmables in a few zones. There were changes to the density of several types of nodes in several zones, which seems to have had a net effect of reducing the overall raw materials coming into the economy. I don't know about on your realm, but for the first day of Cataclysm on Drenden, the amount of ore and herbs being posted on the auction house was surreal. There was a day or so that I could get elementium ore for 85g. It skyrocketed back up after the changes and has steadily been falling since then. The most hard hit was Twilight Jasmine nodes in the Twilight Highlands, as there is no other place to farm them.
There was a also bug on release where Ethereal Ink was costing 10 Blackfallow Ink instead of the intended one at the Dalaran Ink Trader. This might have messed with the glyph market a little; however, I don't think many people were buying new glyphs when the expansion went live but were questing and leveling instead. In any case, Blackfallow Ink is still far too valuable and expensive to be traded down to any lower-level ink. The opportunity cost is a tenth of a Inferno Ink, and I'll bet that if you went and checked right now, those are selling for several hundred gold.
This is somewhat troubling while leveling inscription, because short of having access to Casandra Downs in the phased area of Twilight Highlands, you'll need to be make Runescroll of Fortitude II until it's green while working on getting to 525. If you think that paying five Infernal Inks per green recipe is bad now, imagine how people felt trying to level before Blizzard hotfixed the recipe to actually grant skillups. I imagine the next step is to fix it so it actually applies the correct amount of bonus stamina instead of 165.
Enchanting mats were a little messed up on release, too. For a while, weapons (which usually have a higher chance to drop essences) were disenchanting into mostly dust, and armor was dropping mostly essences. This was in effect for long enough that the data you see on sites like Wowhead.com is probably incorrect. Right now, weapons are dropping essences and armor is dropping dust. This greatly reduced the price for Hypnotic Dust, which is called for in a much greater ratio than essences in most enchants.
Another important bug fix was that until somewhat recently, people were able to attach Eternal Belt Buckles to any Cataclysm gear, negating the need for the much more expensive Ebonsteel Belt Buckle. It's been fixed now, so blacksmiths are again happily churning out the new versions (assuming they've paid their five Pyrite Bars to the phased level 84+ vendor).
Lastly, the Vial of the Sands is now BoE. Instead of being an alchemist-only perk mount like the flying machine was for engineers, it's now a status symbol with a passenger car like the chopper was. The recipe is a low-chance drop from the Canopic Jar, and you may or may not be able to see it if you aren't an alchemist. Once you get it, you still have to make it -- and in good gold sink tradition, this means thousands of gold sunk into vendors, as well as some player-made items.
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