On a hunch I posted all of my wrath of the lich king meta gems on the second day of cataclysm. They all sold. ALL OF THEM. Especially the chaotic skyflares (dps meta gem) which were rolling out at 97 gold a pop. Speaking of wotlk jewelcrafting items for sale, uncut epic gems are selling to all those players trying to get easy skill ups as well.
Other "old" world items have been doing sensationally well such as your standard set of glyphs which people left to buying until the last minute. Makes me wish I had sold LESS during glyphmas because I have never seen so many glyphs going for 200 gold EVER. The first glyphmas was great but lacked the sense of urgency that this one has in the buyer base.
Speaking of inscription, have you been selling all your snowfall inks to scribes trying to get some easy skill ups from darkmoon faire cards? I sure have!
That's the selling end... what about the buying end? Well I've been purchasing dirt cheap abyss crystals and converting them into dust/essences to sell to levelers.
I have only leveled Markco to 82, after which I realized that leveling and crafting just isn't worth the time at the moment. You're better off getting your farming time in and selling as much as possible. How you sell is important as well, because I'm seeing a lot of people forgetting their Markco-vian economics course already.
Cataclysm Economics 101
Don't try to be the lowest seller.
Factor in the demand for the item as well as the supply.
Post a few gold above the lowest person or post right at the middle of the pack.
So many people are trying to post at the very lowest amount and getting owned by auctioneers like myself who buy them out and relist the new cataclysm items for their proper values. Hypnotic dust is not infinite dust! It is worth far more than the essences of the same item level (unlike wotlk dust to essence ratios). You're going to find lots and lots of Celestial Essences but very few Hypnotic dusts in your travels around cataclysm. So price accordingly and understand that Hypnotic dust is where you can price gouge like mad.
Interestingly enough, Blizzard has nerfed the oh too numerous amount of ore in Uldum which is a shame because I found that mining route to be the best by far. I'm curious to see if ore gets higher due to this change and also the surge of players entering cataclysm for the first time this weekend.
Have you been playing the auction house or are you spending all your time leveling? What are you up to at the start of cataclysm?
Guide Update: The best skinning spots, volatile locations, overall farming spots and much more have been added to the gold guide. In the wotlk version of 20k leveling I steered clear of farming spots but in cataclysm they will be added tothe guide for those of you who would rather farm than play the auction house.