One of the little things i’ve already noticed in my limited play time post 3.0.2 is the change to Arcane Torrent. This is a blood elf racial ability. I never used to bother using it or Mana Tap previously as they were pretty useless, but the new Arcane Torment if not awesome at least can be used now.
3.0.2 Arcane Torrent – Silence all enemies within 8 yards for 2 sec and restores 6% of your Mana.
This is on a 2 minute cool down and does not activate the global cool down (GCD). This last bit is what makes this actually useful. 6% mana return is nice, but being able to use it without activating the GCD is handy. What i’ve done is add it to my Inner Focus macro. This goes something like this:
#show Inner Focus
/use Ancient Crystal Talisman
/cast Arcane Torrent
/cast Inner Focus
What this does is use my trinket (Ancient Crystal Talisman) which boosts my spell power by 104, then cast Arcane Torrent (giving me 6% man return) then cast Inner Focus. It does all this instantly and without activating the GCD so i can cast a Greater Heal or offensive spell straight after it. Although the 6% mana return is sometimes wasted, by having it in this macro I at least the ability fairly regularly.
Other ideas would be to add it to either a macro with your Shadowfiend or even you mana potions, for extra mana return. This would ensure better use of the 6% mana return, but might mean that you waste it during long fights while Shadowfiend is on its 5min CD or the mana pots are disabled due to the invisible potion sickness.
Edit: Arcane Torrent is returning about 457 mana per use. My mana pool is about 7,800 at level 67.