Diablo 3 Demon Hunter

Only a limited amount of skills were actually released for the Demon Hunter at Blizzcon.  Drumroll please…

Tier One Skills

All abilities in this tier are unlocked at level 2.

Bola Shot

The Demon Hunter uses a bow or crossbow to fire a spinning projectile; two bombs on a length of rope. The Bola hits the target and wraps around it, dealing minimal impact damage but considerably more explosive damage after a couple of seconds.

• Description: Shoot out an explosive Bola that wraps itself around its target. After X seconds the Bola explodes, dealing X% weapon damage to the target and an additional X% weapon damage to all targets within X feet.

Grenades

Grenades are small projectiles thrown by the Demon Hunter. They bounce around, ricocheting off of walls and other obstacles, before exploding a couple of seconds after they are thrown. They deal considerable fire damage, but are hard to aim precisely, and are best used against large mobs, especially to hit targets located in the back row.

• Description: Throw out three grenades that explode for X-X fire damage.

Tier Two Skills

All abilities in this tier are unlocked at level 3.

Entangling Shot

This debuff skill deals solid damage, as well as slowing the target. Nearby enemies may be chained as well, potentially slowing several monsters and blocking the movement of all that are stuck behind them.

• Description: Release a sticky adhesive that deals X% weapon damage and entangles up to X enemies, slowing their movement speed by X% for X seconds.

Spike Trap

This trap/object is placed and triggers when enemies move into range.

• Description: Lay a trap that arms after X seconds and triggers when an enemy approaches. The explosion does X-X damage per second to all enemies within X feet for X seconds.
• You can have a maximum for X traps active at one time.

Tier Three Skills

All abilities in this tier are unlocked at level 6.

Vault

A fast movement skill, this allows the Demon Hunter to move a considerable distance at high speed, passing through monsters and other players, though not through solid objects or over open space.

• Description: Tumble acrobatically X feet.

Fan of Knives

This skill, instantly nicknamed “knife nova,” shoots out numerous blades, dealing considerable physical damage to any targets nearby. The range is very short, hardly more than a melee weapon, making this one best used in very close range against multiple targets.

• Description: Throw knives out in a spiral around you doing X-X damage to all enemies within X feet of you. Your knives will also slow enemies by X% for X seconds.

Tier Four Skills

All abilities in this tier are unlocked at level 10.

Molten Arrow

Molten Arrow deals heavy fire damage, pierces all targets, and leaves a trail of flames behind it, dealing AoE damage to any enemy who walks over them. A very useful skill against large mobs, especially when lined up as in a narrow passageway.

• Description: Shoot a piercing arrow that hits targets for X% weapon damage and leaves a trail of fire dealing X-X fire damage per second to all enemies who stand in it.

Multishot

The Diablo II favorite returns. This skill fires a huge cluster of arrows or bolts, guaranteeing a hit on everything in range. The mana cost is fairly high and the damage is lower than most single arrow attacks, making it best used against huge groups.

• Description: Fire a massive volley of arrows dealing X% weapon damage.

Tier Five Skills

All abilities in this tier are unlocked at level 14.

Shock Spike

A booby trap skill, this one leaves mechanical contraptions on the ground that spin, dealing cutting damage to enemies in range. Multiple Shock Spikes hurl saw blades back and forth, cutting enemies that attempt to pass between them.

• Description: Place up to X mechanical contraptions on the ground. The contraptions spin and deal X-X damage to all nearby enemies. The contraptions also generate sawblades between them that deal damage to enemies in their path.

There are also Tier 6 and 7 skills, available at levels 20 and 26 respectively, but none have been released for this class as of yet.

Big thanks to diablowiki for the skill descriptions.