However, I think the latest buff to UtH may have been a little bit overboard.
In a Vacuum, Unleash the Hounds is most comparable to Arcane Explosion. 1 damage for every creature an opponent controls, with the tradeoff of having to dodge taunters for the ability to gang up on a single target. From this view, it makes perfect sense that Unleash the hounds should cost 2 instead of its original 4.
However, what this vacuum view fails to take into consideration is that Hunters have a great number of other tools, low cost tools at that, at their disposal to use UtH in other ways. Timber Wolf is not the worst offender here, as he might as well read +1 spell damage. Instead it's the cards Scavenging Hyena and Starving Buzzard that can turn a four mana investment into drawing 2-4 cards or an 8/5 Hyena in addition to summoning your hounds.
The real issue here is not so much that this combo exists, it's that these combos can be played on turn four with no time to react from the opponent.
I believe that 3 is a more reasonable cost for such powerful utility.