New glyphs for 3.1 have been announced for testing. The tanking ones are:
Glyph of Heroic Strike -- Increases the critical strike chance of Heroic Strike by 5%. (Old: You gain 10 rage when you critically strike with your Heroic Strike ability.)
Glyph of Barbaric Insults -- Your Mocking Blow ability generates 100% additional threat. (Old: Your Mocking Blow ability also taunts the target.)
Glyph of Shockwave *new* -- Reduces the cooldown on Shockwave by 3 sec.
Glyph of Vigilance *new* -- Your Vigilance ability transfers an additional 5% of your target's threat to you.
Glyph of Enraged Regeneration *new* -- Your Enraged Regeneration ability heals for an additional 10% of your health over its duration.
Glyph of Spell Reflection *new* -- Reduces the cooldown on Spell Reflection by 1 sec.
Glyph of Shield Wall *new* -- Reduces the cooldown on Shield Wall by 3 min, but Shield Wall now only reduces damage taken by 40%.
On the basis that [Glyph of Blocking] will continue to be mandatory, this leaves 2 major slots. The shield wall glyph is so good that unless it is nerfed before it goes live then that too will be necessary. This leaves one slot.
The other glyph is pretty much a matter of personal choice, and in fact it may be necessary to reglyoh for specific fights. I like the enraged regen glyph as a noticeable improvement in one of our "oh sh*t" buttons, but the vigilance glyph will be useful if as predicted our ability to generate threat fails to scale at the same rate as the dps classes.