HS is only beneficial if you fight 2-3 mobs and even then using IT more often is still the better idea. If you find yourself fighting 3-4 mobs a lot and having serious aggro issues move the 3 points out of http://wotlk.openwow.com/spell=49395 and move them to http://wotlk.openwow.com/spell=49467 instead. Tab through targets and use IT all the way.
HS is not imperative, but its very useful for AOE threat, since it hits multiple targets.
This is my blood tanking spec, and it works for me, I don't know what others think about this. http://wotlk.openwow.com/talent#j0EM...soZhg0x0MZ0xhb
Frost presence always.
I would suggest getting: [Sigil of the Frozen Conscience], from Grizzly Hills: Venture Bay.
If u have any aggro problems, this will solve everything.
It increases the DMG of Icy Touch by 111 so its gona boost ur threat by a lot, and its easy to get, 3 daily quests and ggwp.
As far as for AoE tanking (dungeon tanking, or spec for clearing the trash in ICC if u can aford it), u cant do much since DnD is bugged, aka making less Threat than its suposed to. Get Glyph of DnD, get Sigil of the Frozen Conscience, and spam **** ton of Icy Touches with some Death and Decays.
This spec can do the trick... http://wotlk.openwow.com/talent#j0E0...xxVMIk00buZcbu
Try to convert ur normal runes to death runes as much runes as posible, especialy when u have solid agro and u are about to pull the new pack. After that spam Icy Touch on each one of ur targets followed with Death and Decay and u should be fine more or less.
Edit:
As far as for Heart Strike goes, its pure crap. It does not give any kind of extra Threat as much as i know... Deals almost the same DMG as both Blood Strike and Blood Boil when it comes to the main target, every single one of these abilities make almost no Threat, deals far less DMG than Blood Boil on secondary target, it doesnt hit anything else.
Thats actualy true, completely forgot about that... Good advice. :D
Lady, Sindra, Halion, those are the bossses with parry haste, so i guess u can equip Two Handed weapons on those.