There is a big difference between "Tanking Gear" and "Boosting Gear". When you tank you want high mitigation - block - dodge - parry - miss (defense provides all of these BTW), then high stamina, high armor, then spell power- basically. We could get into more details and discuss this forever, but this is basicall correct.

When boosting you want High armor, high stamina, high spell power. The mobs will not crit you nekkid. The higher your armor, the lower their damage when they do hit you. High stamina allows you to collect crazy amounts of mobs by running around (you loose the most health with your back turned because you can't dodge, block or parry). And you want high spell power to 1. kill mobs faster and 2. heal yourself for more if you have to. With ret aura up you want mobs to hit you, it kills them faster. With the cange to BoS (which I love) if you have enough mobs you will never run out of mana, even with the downranking nerf. You can still cast rank 1 consecrate to gather mobs, they will give you your mana back and then some.

The best gear for this is the PvP S2 honor gear. Very high armor and stamina and good spell power. The Seasonal gear is also easy to pick up, in season. The brewfest trinkets were nice and the rings from HH are very good if you are a fresh 70 (or will be soon). I personally heal in BGs as prot spec and have been effective since my mid 60s in AV. I mostly am too cheap to respec very often. If you would rather kill stuff, spec Ret. But when you get your gear keep boosting in mind. Honor rolls in very fast now and each peice makes it easier.

If you are going to take the pally to 80 - or even 71+. You will probably get better gear in Northrend, or maybe in the AH from Northrend. Something else to think about.