@Brian23
For 1.
Sadly only pure melee damage so on several special boss abilities (Hard Stare, Triple Puncture) you're better of with barrier if you're in danger of not surviving the very next swing/want to help your healers out/etc. The crux: every time you don't hit block your hardest hitting abilitiy (shield slam) hits for 50% less thanks to a major glyph, so when you're maximising outgoing damage that's a good point to start.
On 10M heroic content there's another problem: the raid damage flying around. While you can block the regular swings from a boss all the cones, dots, auras hurting you come in totally unmitigated. If you use barrier instead you could prevent/absorb over half of your incoming damage (at the cost of a part of your damage dealt, as explained above).
For 2.
Just to give you the picture (numbers from todays
raidbot 10HC for the last two weeks):
267k monks
237k paladin
229k dk
215k druid
152k warrior
That's with the data used from the top 100 logs for each class/specc and the picture drawn is just plain horrible. We should end up getting a damage increase in the 2x% area from additional critical strike chance, more enrage uptime, more thunderclap damage and superior Ultimatum proccs. But please do the math, 152 times 1,25 is 190k. Unless they also increase the scaling and/or base damage on
all of our abilities we'll have a very hard time competing for the damage charts. On the damage intake side on the other hand we should shine with the new t16 bonus & crit block cap, but Blizzard can't tune boss' around crazy damage intake figures, in the end everyone needs to able to survive a certain situation. And if you don't die from it on the spot you'll have to justify why you'd want to bring a tank that deals x damage when another tank deals y damage (and in this extreme scenarior of warrior vs monk it's almost y=x+a full dps slot).
Ps: I really don't see your argument pro warrior. While playing on a monk you have superior frontload damage reduction against anything (including bleeds~) from stagger/shuffle, superior healing and it's totally controlable with expel harm, guard and purifying brew (especially with current 4 piece). All the hassle with monk is from the pull when you don't have your AM rolling.