I know no one asked this, but I would toss this out there. I figure anyone interested in the above information, would enjoy this Crit information:
125 Defense is needed to negate the base 5% crit rate, mobs your same level use this. For each level above you, you need 5 more points of defense to negate. For us, our math looks like this:
350 (base for a 70) + 15 (5x3 since raid mobs are 73) + 125 = 490 (the magic number)
Druids get Survival of the Fittest, it lowers there chance to get a crit by 3%. That means they need the same 15 + 50. They only need to negate 2%. This is why they only need 415 defense skill.
Also here is some nice information about Ratings, and how they effect Dodge, miss, parry, and block:
Rating Effect Required 60/70
Defense 1 defense Sk 1.5 2.37
Dodge 1% dodge 12 18.923
Parry 1% parry 15 22.4
Block 1% block 5 7.88