Given the extreme lack of available tanks in comparison to other classes, especially DPS it should be pretty clear that tanking classes need some sort of "homogenization". And by homogenization I mean they need to be more than a punching bag.
I'm sure all of these changes are going to result in more players rolling tanks. Maybe not a substantial amount at first but it'll surely be better than things currently are.
Besides, this certainly isn't the first time tanks have been using dps weapons, take note of the best tanking weapon available pre-bc, Thunderfury. It wasn't the best tanking weapon because it had the best stats for tanking.
And finally to completely counter your argument when it comes down to it being able to spec so you simply have a ton of HP and get threat simply by virtue of being in a specific stance or something IS LAZY. You should have to work for your aggro. You should have to compete against dps to hold that aggro.
That's the one and only reason I don't hate DK tanks most of them I do, because almost all of the players rolling them are total retards especially if they choose to dual wield. But they're actually a bit fun to play because their threat generation is based more off of DPS than any other tanking class.
When I'm on my warrior the only time I enjoy tanking is when I'm off tanking in hybrid arms spec. Because my ability to tank isn't just a matter of me simply being a walking punching bag and I enjoy competing against dps to maintain threat. It was awesome in 3.1 when I could MT some bosses in that spec like Malygos and maintain 4k+ dps. That was fun.
So between this and Blizz's talk about changing misdirection and tricks so it's not simply more free threat for your tank I for one am very excited about this. Tanking might actually be fun in Cataclysm, imagine that.