Holding aggro - absolutely not an issue except for Malygos
Decent DPS (tied to generating massive aggro) new fun challange
Reaction time/ Positioning / raid leading unchanged.
Since most guilds have the content on farm you miss out a bit on the excitement unless you group with a guild that is still struggling with naxx or malygos - since you are an ex sunwell tank you probably would hate those guilds.
join now and get in line to tank Ulduar content, Naxx is old news.
Unfortunately, there are allot of snarky posts, or at least posts that read as snarky when they should be read as humorous/ sarcastic.
I am guilty of both being read as and in reading posts in this manner.
Back to your origional question though, yoru miles ahead of me as far as tanking content if you were doign SunWell, my guild has never been able to field enough folks to try it. In LK we mainly just do Naxx 10 for folks and the heroics.
One day I'd like to hit EoE though.
The challenge, at least for me lately, has been in figuring out how to max my DPS without gimping my Defense stats.
Its sorta like playing Gran Turismo but with Armor. (If your into racing games that is)
Around 50% of the solid DPSers. 2k for me, with most DPSers around me that are worthwhile doing around 4k. High end tanks are doing over 3k, but high end dps is pushing over 6k. Tanking is alot more reactive for warriors now, you have to watch your procs and cooldowns and adjust on the fly to max your dps, its more than just doing your normal rotation, waiting for 50+ rage and heroic strike, which is a Good Thing IMO. I don't believe a chimp would follow the priority list correctly, but could definetly hold aggro over the typical pug. If I pug a heroic I am typically #2 on dps and #1 on damage done.
TPS has been easy for me, I let DPS open up with their big threat moves and never worry about threat dumps. But since I'm trying to max my DPS, I am also maxxing my TPS. There's no more silly, I'm going to pick a low dps but high threat move to max out threat, except thunderclap. I think that is why its typically reported that threat is easy. I have certainly seen tanks have aggro problems against serious DPS. They also had poor rotations, poor gearing, and poor situational awareness. AoE threat is more about thunderclap/shockwave, but tab targetted is still required if you want to hold aggro on AoE that is serious. I'd say threat depends more on the tank knowing what they're doing, rather than the dps constantly fighting omen.
Interesting, what kind of DPS are tanks pushing these days?
It depends on the fight. In a fight in which you intake regular damage and can freely use rage abilities, 2500 DPS is pretty reasonable. Over a whole heroic 5 man I would say 1600 is more likely since you cannot stand still all that often.
With me specced prot and playing 2nd OT (My guild is Prot Tank heavy), I generally come in at 6th or 7th out of the 10. Which sucks I know, beleive me I know.
The rankings aren't that important. Tanks are still meant to be at the bottom relatively speaking... they just aren't supposed to be fighting with healers anymore for not last.
On the topic of threat:
We have a slightly greater than 2x threat multiplier. Almost every dps has a stance multiplier less than 1 (ignoring aggro dumps). So it's possible that Blizzard is tuning tanks at 50% of dps-ers dps for theat purposes.
However, just like there are dps-ers who can't break 2k dps with epics if their life depended on it, there are also tanks who can't hit 50% damage of a mage blasting 7k dps despite being equally geared.
What I'm saying is this tuning assumes similar gear and skill. Scrub tanks won't be able to hold aggro on good players. Good tanks might not even be able to hold aggro on players that outgear them (especially as more raid content gets released).