In the Patch 3.2.2 PTR files, a number of new race/class combination NPCs were discovered. The data mined from MMO-Champion seems to indicate that several races will have the ability to roll classes previously unavailable to them. However, it is only speculation that these combinations will be playable, but with the addition of the class-related quests with each additional patch, it seems quite likely.....
* Human Hunter
* Orc Mage
* Night Elf Mage
* Blood Elf Warrior
* Dwarf Shaman
* Dwarf Mage
* Undead Hunter
* Tauren Paladin
* Tauren Priest
* Gnome Priest
* Troll Druid
* Human Hunter
* Orc Mage
* Night Elf Mage
* Blood Elf Warrior
* Dwarf Shaman
* Dwarf Mage
* Undead Hunter
* Tauren Paladin
* Tauren Priest
* Gnome Priest
* Troll Druid