Nothing about the stat changes seems fun or exciting to me at the moment, as someone who enjoys playing Warrior/Paladin.

Plate doesn't mitigate much more then cloth.
No HP advantage
Fun factor completely removed from using a shield.

This one bugs me the most, the shield mechanic in it's current form is a lot of fun, in cataclysm it'll be about as meaningless as a ranged weapon on a warrior, providing a flat DR that every other tank gets from talents / skills.

Basically in Cata all tanks will be exactly the same except they'll look a little different and their spell effects will have different colors.

Not fun.

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Q u o t e:
I enjoy being able to stack SBV pop trinkets / Abilities and block a huge amount of damage for a short time
and being able to fully block attacks from lower level mobs, all of which will be impossible in cataclysm.

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You'll still be able to line up trinkets and abilities to get really good blocks when you need them. We think this design will let us make blocks more meaningful to the tanking experience since you could actually block 20,000 or more damage on a 60,000 hit.

Being able to trivialize lower level mobs is sort of a bizarre perk though (and one not shared by all tank classes) and not something we're really interested in preserving.