The Darkmoon Faire has finished, so there should be more cata herbs available for alchemy.
However, there is a new herb sink with the recent changes to the guild achievement Mix Master, allowing guild members to learn the 'Couldron of Battle'. 10,000 flasks was a big ask, but with the recent reduction down to 1000 flasks, this is now affordable - for those with deep pockets. The guild I am in is Level 11 with Chug a Lug (bonus flask duration), so Guild Cauldrons have become even more attractive. But 1000 flasks is still a lot of herbs and a bit of volatile life. Flasks also sell for less than mats (and personlly I prefer two elixirs - the total buff is meant to be better).
Each guild needs 1000 cataclysm flasks. Each flask takes 24 herbs, and 6 volatile life. 24,000 herbs + 6000 life is a lot for each guild to pull out of the auction house.
If you are not an achievement junky, check your prices before making flasks. Of course, if you are after the achievement, go for it.
One final note: Gold bloggers occasionally talk about resetting prices on the AH, with the biggest drawback being offloading your excess stock, plus other players unloading theirs at the new prices. With purchasing herbs for Mix Master there is every chance you will reset the AH prices, possibly draining other players stockpiles. It will take a while for the AH to 'respawn' replacement herbs. If you finally end up with too many herbs, sell your excess back at the new prices.
It must have been her period - You probably heard that I'm trying to clear the normal and heroic content of WoW without having a guild or fixed raiding groups, just with PuGs. It's going...
8 hours ago