I loved...loooved melee weapons and unarmed in FO3 whereas they just kind of pissed me off in the first two games.
Definitely my fighting style of choice for evil playthroughs. It just makes it a whole lot personal and brutal when you cut some poor bastard's head or limbs off with a power fist or an auto axe instead of discreetly blowing them away with your pistol or rifle.
So I'm particularly giddy at the addition of new special attacks. Doesn't quite make up for the inability to target body parts in VATS but close enough.
You can target specific body parts. I don't think you can target specific limbs with the special attacks, but you can with regular ones. I'm hoping that they varied up the regular swinging and punching animations. Throwing the same two punches or just swinging your weapon back and forth looks pretty terrible. Maybe they could have it so as you increase your skill your combat animations are more varied and maybe faster. If your character doesn't really know how to fight, their attacks should be slow and imprecise. A highly skilled Melee or Unarmed character should be fighting like a ninja.