How to make profit. I did this and got around 500k in 1 Week of farmin when Cataclysm realeased.

Step 1- Have an alt with Mining + Herb (pref Paladin like my alt),
Step 2- Go nuts and farm like hell after u dinged ur first 90 or before that (remember the first 3 days in cata realease the node respawn was INSANE)
Step 3- Since Node respawn will be Insane, prices will be low on ah the first week. During cata i bought Twilight jasmine for 20g/stack at release week, and Elementium ore for 15g/stack. So have a Second alt Stay at ah and allways check it for good prices
Step 4- Use ur Proffs on other alt like i did Jc and Inscription on Main. Jc for Prospect - Gems, Ppl want 2 lvl Jc so gems will sell as hell! But 2 the biggest one, Inscription - Milling. I was the first one with Darkmoon Decks out on ah, i sold the first ones (dps/healing) for 40k each! and tanking/meleedps for 25-30k.
Step 5- HUGE PROFIT!

I spent around 30k herbs mats on ah and farmed directly as Cataclysm hitted and got the early Noderespawn, Inscription maybe made me 420k in the first Week.

Note: Ofc u can get the decks, wait for Faire and turn em in and wait untill faire is gone, that will make price slitley go up since its only for 1 week each month.

Sorry for my english, i hope this helps making gold. I did this only for 1 week, i also lvled at the same time when i got bored on farming.

Gl in MoP