I've been looking at my crystal ball, and I think I see a few things.
I expect that there will be new tanking glyphs. New glyphs give players additional choice, and will 'allow' tanks some options for mitigation. These 'choices' are in reality likely to be mandatory.
Scribes will be able to learn all research major and prime glyphs from either Books of glyph mastery (no cooldown), or via "northrend" research (or a similarly named skill). While this has already been flagged as something that will happen, I expect it to occur in patch 4.3.
If the combinations of the above two items are true, then there should be a short term increase in demand for Books of glyph mastery, followed by a sustained and significant fall in demand.
I think there is a possibility that "northrend" research will be renamed, and will require inferno ink instead of snowfall ink. If this occurs, the price of snowfall ink will plumet, and inferno ink will rise temporarily. This in turn will lead to a shortage of 'cheap' crafted trinkets, and possibly a fall in the value of volatile life.
Crystal balls are interesting things, and are generally subject to interpretation. This community has only middling luck with predicting
future pricing; and even when we do guess things correctly - we tend to
over stockpile, causing the opposite effect of what was forseen.