Step through the shadows from enemy to enemy within 10 yards, attacking an enemy every .5 secs with both weapons until 5 assaults are made. Can hit the same target multiple times. Cannot hit invisible or stealthed targets.
Killing Spree Is the final talent for combatrogues. This talent is an instant rogue ability that allows to deal a large amount of burst damage to one or more enemies in range.
Notes
While Killing Spree is active, all enemis will de-target the rogue, practically renderingthe rogue immune to direct damage abilities. Note that Area of Effects and existing Damage over Time debuffs will still hit the rogue.
If there is more than one enemy in range, you may end up at the enemy you don't want to attack at the moment.
Killing Spree deals more damage with slow hitting weapons.
Deals incredible damage to single targets, and can be used to handle mobs efficiently when combined with Blade Flurry.
Can hit players on flying mounts and is commonly used for aerial ganking, since Killing Spree prevents falling by constantly teleporting you back to the floating victim. (See video)
Also assaults neutral targets (like critters), so beware before you use Killing Spree.
Killing Spree works with Blade Flurry, so popping both can give five large hits on two nearby enemies each, and as such is very useful for tight situations. In other words, Killing Spree with Blade Flurry is similar to AoE.
During Killing Spree, you continue to melee. Slice and Dice and/or Blade Flurry should be used in conjunction with Killing Spree because of this and the 20% damage bonus of Killing Spree.
Rogues have been witnessed falling off the catwalks in the Upper Reaches of ICC while using it.
Patch changes
Patch 3.2.0 (2009-08-04): Error message when no targets are in range has been changed to "Out of Range."
Patch 3.1.0 (2009-04-14): Now also increases all damage done by the rogue while active by 20%.
Patch 3.0.8 (2009-01-20): This ability no longer breaks stealth if it fails due to all targets being out of range.
Patch 3.0.3 (2008-11-04): Instead of making the rogue untargetable, now causes all players to lose targeting on the rogue and the rogue to be unstoppable during its duration.
[Tricks of the Trade], Killing Spree can make for some great pulls.
Patch 3.2.0 (2009-08-04): Error message when no targets are in range has been changed to "Out of Range." 
Patch 3.1.0 (2009-04-14): Now also increases all damage done by the rogue while active by 20%. 
