Rogue 80 Expertise Cap

Expertise, why?

Expertise basically dictates if a boss can dodge or parry a melee attack.
Its basically understood that a boss has a 6.5% "Soft cap" chance to dodge a melee attack and 14% "Hard cap" chance to parry an attack.
As Rogues, unless their threat meter blows their eardrums apart, do not act as main tanks (Yes I have seen a Rogue with 104% dodge MT a raid!), lets be concerned with the "Soft cap".

Expertise Rating
Expertise rating is generally from gear stats. (eg Conqueror's Terrorblade Breastplate)
For each "32.78998947" in expertise rating at level 80, you reduce your chance to be dodged/parried by 1%.

Therefore 32.78998947 x 6.5 = 214 Expertise Rating to reach the "soft cap".

Expertise
Expertise is generally gained from talents. (eg Weapon Expertise)
For each point "1" in expertise, you reduce your chance to be dodged/parried by 0.25%.

Therefore 6.5% / 0.25% = 26 Expertise to reach the "soft cap".

Where do you find this?
In your Character page at the bottom between all your l33t gears will be your melee stats.
They will read:

• Damage: xxxx-xxxx
• Speed: x.xx/x.xx
  
• Power: xxxx
  
• Hit Rating: xxx
  
• Crit Chance: xx.xx%
  
• Expertise: 26/26

Rogue Level 80 Expertise cap 26!

Again it isn't critical to hit this on the mark, however exceeding the cap will do zip to help your dps.