Warning : In Wrath of the Lich King, Perception became a passive racial. In TBC, this is an ability that you have to use strategically. Smart opponents have multiple ways to make you waste your perception such as: using pre-vanish opener, AoE (arcane explosion or Flare for example), Paranoia (Lock) or even…. waiting for your buff to fade out.
Specializations
The expertise with swords and maces is a nice bonus for PvP but more useful in PvE. It allows you to reach your expertise cap more easily. For more information about expertise and caps, have a look at our Theorycraft guide about Hit and Expertise as Rogue.
Diplomacy is also quite useful for reputation grinding. As a rogue, you will be interested in Aldor and Hyjal reputations. Being able to grind Karazhan’s reputation faster with a fresh 70 character is also quite nice, the same goes for Heroic mode dungeons.