Expertise:
The value of expertise seems to elude some people, to make it simple;
in pve, raidbosses have a chance to dodge your attacks even though you stand behind them, with expertise, you can negate this.
Bosses have a 6.25% - 6.50% chance to dodge your attacks, this goes for all main attacks (mutilate I.E,) all finishers and white damage.
Each point of expertise gives you a 0.25% reduction on being dodged.
with no racials,
you will need 214 expertise rating from gear, or 26 expertise points.
with no racials, but 2/2
Weapon Expertise:
you will need 132 expertise rating from gear, or 16 expertise points.
With the human racial wielding either swords or fists, and specced into
Weapon Expertise:
you will need 107 expertise rating from gear, or 13 expertise points.
simply put, no matter what racials or talents you are using, if you read 26/26 expertise in your character tab, you are capped.