Was reading the beta forums again and there's a thread about spiritwalkers grace not being too useful for pvp.
I don't think that's true, especially in arena settings for resto and ele and even enhance can use it as a anti kiting ability with hex.
It could be better and would improve shaman and especially enhancement game play if it made us immune to Roots, stuns, charms, knock backs, and knock downs.
Everything besides snares/slows, fear, and poly.