That's an interesting question...I hadn't heard anything about this until now.
Frankly, I had been wondering about how the more "valuable" glyph recipes would be obtained. The thought of them being purchased through rep vendors is enough to make me shudder, since the last thing I have time for between now and the patch is grinding rep.
Edit, because I was curious:
Source:
WotLKWiki Scroll down to the "Abilities" section.
From what I can piece together, Decipher does function like Disenchanting in a roundabout way. Scribes will get two abilities: Northrend Inscription Research (requires 400 Inscription skill) and Minor Inscription Research (requires 125 Inscription skill). Those are the abilities on the 20 hour cooldown, and when used, will create random scrolls. You would then most likely apply the Decipher skill to those scrolls for a chance to learn a new Glyph recipe (minor glyph from scrolls acquired through Minor research, major glyph from Northrend research scrolls).
Also, take a look at the item in the bottom middle of this screenshot:
here It's impossible to tell whether that item ("Floral Foundations") came from research, or whether it was one of the odd results reported by some folks while milling herbs.
Either way, it sounds like Blizzard is doing their best to make Inscription more interesting than simply "get recipes from trainer/world drop/dungeon boss/rep vendor, mill herbs, make Glyph, repeat". Kinda cool so far.
Edited, Sep 27th 2008 2:45pm by AureliusSir Edited, Sep 27th 2008 2:46pm by AureliusSir