for other ideas on the glyph market please follow the link to the free Croda's Inscription Gold Guide
On my server herbs are now running in short supply and the prices have moved up to 2gold a whiptail (40gold a stack) if i am lucky. And that includes the weekend.
Two things happening here.
Firstly, demand for glyphs (and potions) has been low in the pre new content slowness hence herb farmers are absent from the market. Thus supply of herbs is severely restricted.
Secondly, people, including myself, are slowly starting to stock up for Mist of Pandaria. Hence, a new demand for herbs that is unrelated to the current demand for glyphs (and potions). Indeed, i am picking up herbs of almost any type that go for 1.5gold (30 gold a stack). Worth noting that on my server the herbs for Shimmering Ink and Jadefire Ink i can get for 1gold (20 gold a stack) quite easily.
Perhaps during the holidays i will get the chance to buy herbs cheaper. But at the moment i am slowly building up my stocks for the new content.
I can already see the effect of holiday players when i see Northrend herbs (Ancient Lichen , Dreaming Glory, Felweed , Mana Thistle , Netherbloom , Nightmare Vine , Ragveil and Terocone) put on the Auction House for 1gold (20 gold a stack).
The good news is that this is forcing the price of glyphs up. Though mainly because a competitor is running short of herbs to mill. The demand for glyphs remains unchanged and lowish.