I've seen Utamar, Pwootytat and Inevitabull (Idiote) do some pretty tight stuff with druid heals. I wouldn't mind having a resto druid as a healer in WSG if the players know what they're doing, and that's the problem -- most people don't. For newer players, priest may be the best choice; I feel as if they're the easiest to play out of the healer specs.