I've been doing some of the new Hyjal dailies and I noticed a random buff after a few minutes. The buff states that your next ability that has a chance to critically strike will do so. I'm currently on my boomkin, yet... 99% of the time my next ability will not crit at all. The buff stays there until I do, however, get a critical strike by RNG. Then it goes away until I pass through another ghastly elk-looking creature.