There is four different rogue speccs at level 19 now.
Ambush / Backstab
Glyph of Backstab
Use: Increases the damage dealt by Backstab to stunned and incapacitated targets by 20%.
If playing with a druid or mage, this glyph is lethal, freeze / root will give your backstab a 20% dmg increase.
Combat & Sinister
Glyph of Sinister Strike
Use: Your Sinister Strike critical strikes have a 50% chance to add an additional combo point.
Let the combo points flow as you spam your "2-2-2-2-2-2-2"
Garrote / Dot
Glyph of Garrote
Use: Reduces the duration of your Garrote ability by 3 sec and increases the total damage it deals by 20%.
You're garrote will slowly tear your enemy to pieces, sick damage imo.
Eviscerape
Glyph of Eviscerate
Use: Increases the critical strike chance of Eviscerate by 10%.
With these glyph your Eviscerate will gain a 10 % crit chance which grants you to tear opponents apart.