I don't know.
www.wowconfidential.com says in 4-0-3 jessica sellers now trades only blackfallow ink for other inks, in turn quoting WoW insider and MMO champion.
I am expecting another fortnight of Nothrend herb gathering, plus a couple of weeks of herb dumping come the Cataclysm. I am relying on this to produce Ink of the sea. I have converted all of my existing Ink of the sea down. I already had guild bank tabs of herbs, and I bought about 5000g of herbs last night. I will busily mill more inks tonight before shutdown (and I don't normally do milling). I wont be able to mill everything before shutdown.
I already have a large stockpile of glyphs (most of which I have more than 30), I use KTQ and Gnomeworks, with /ktq queue 50 glyphs to give me an approximate weighting of what type of inks I should stock. If that sounds complicated or you dont have those addons, use Breevok's ink weights to know what to buy.
As an inscriptionist, if you only have northrend herbs or northrend inks when Jessica stops trading, you will be at a significant disadvantage. As a levelling alchemist or inscriptionist, you will similarly want to have your levelling pack put together.
If Jessica will play nicely for the next 2 weeks, I will have converted sooner than I needed to. Either way I will need to restock on Ink of the Sea. If Jessica gets upset by the shattering, I will be better off.
Weekend minipost: but, but, but Mittens pinged it's over - When Tora Bushido, leader of Marmite collective lost his mind, The Mittani himself pinged to the CFC that the wars that caused them 2T damage are over. So ...
8 hours ago