Outside of ZG, I can't remember the last boss that I killed that was considered Humanoid. More of a PvP talent IMHO, and not a really great one at that.
I personally find that anything that increases my survivability is more valuable than one that gives me that last little edge on DPS. With bosses and trash hitting harder and harder, I am starting to prefer things like deflection's damage avoidance over the extra hp from Survivalist. This may change in Naxx, if the AoE dmg scales up tremendously, but currently 5% dmg avoidance is greater than the 400hp gain from Survivalist. It feels really nice to dodge/parry a special attack on the pull that you know would have hit for 3k+ . And FD>Explosive trapping with detterance and high dodge/parry can save your mages a significant amount of dmg while AoEing, at least for a little bit.
Course, I'm also Rank 10, and enjoy the pvp side of the game as well.
Current talent build for those who are curious.
http://ctprofiles.net/403122