It uses the lightning animation instead of the normal nature animation.
When compared to a Mage[Frostbolt], this does slightly less DPS. However, when coupled with Lightning Mastery, Lightning Bolt can do more damage at 2 sec cast. However, Frostbolt may be more effective with it's chill effect on enemies, useful in both PvP and PvE.
Lightning Bolt's spell power coefficient is greater than that of [Chain Lightning]. While its maximum damage is initially less than that of the first strike of Chain Lightning, it draws level at approximately 2071 spell power (less if Lightning Bolt is glyphed). Beyond this amount, therefore, Lightning Bolt causes more damage than Chain Lightning to a single target. However, Chain Lightning's shorter cast time prevents Lightning Bolt from ever achieving higher DPS.
Convection reduces the mana cost of Lightning Bolt.
Concussion increases its base damage, while [Stormstrike] increases the damage of the 2 next nature spells after it by 20%.
This is a good spell to start the fight and pull enemies until level 75 when you can learn [Lava Burst]. Untalented and used against a foe with no speed boosting abilities at max range, you can cast 3 Lightning Bolts in the span of time it takes for a mob to reach you. You can even cast a shock just as the 3rd Lightning Bolt finishes casting to max out damage against a pulled, incoming mob.
It is also more likely to use during combat because of its 2.5 second casting time as opposed to other classes' similar function spells ([Shadowbolt], [Fireball]), and is fairly mana-efficient.