Hit and Expertise are both gone, replaced instead with a universally useful secondary stat. Three new secondary stats have been added -- Bonus Armor, which simply increases armor; Multistrike, which grants attacks and abilities a chance to fire an additional time for 30% effectiveness; and Readiness, which reduces the cooldown of several class abilities with long cooldowns. Multistrike works for both damage and healing abilities, making it useful for all classes and specializations. In addition, the amount of role-specific stats is being reduced. Tanks will use Armor, which replaces both Dodge and Parry, and Spirit will be useful only to healers.
But it's the changes to items themselves that sound absolutely intriguing.