I've spoken with a few druids recently who have either just hit 70 and begun looking into tanking, or have been 70 for a while, but just recently specced feral to tank. Many of these druids have had ideas on tanking stats that were either almost right, or completely off track. I figure, heck, why not explain the benefit of the stats:
Strength is a generally unimportant stat for two reasons. The first reason is that all it does is increase your damage, which doesn't matter a whole heck of a lot in bear, and the second reason is that it increases your damage, which doesn't really mean a whole heck of a lot in bear. Yes, it's nice for increasing your threat, but you shouldn't go looking for it because bear threat is already so high, and what we mainly need is mitigation and survival(being that we lack the 'oh shit!' buttons of our other tanking counterparts).
EDIT: I will reiterate that, yes, it is very nice for threat. The more damage we do, the more threat we gain. The same, however, is true of agility where the more crits you do, the better damage you get(10% increased from talents) and the more threat you gain. More on that in the next section, but just know that as you increase your agility and stamina and such, strength is tacked on to your gear. But don't look for it. Be happy that it's there, be thrilled when you see your mangles critting for 1400, but don't go looking. It'll come to you.
Agility does so many things. It increases your dodge (the most important!), your crit (the second most important!) and your armor(...ya, I know, 2 per agility, but hey, it does!). The more you dodge, the less often you are hit, and the easier you are to heal. Your dodge percentage should be about equal to the combined Dodge+parry of a warrior counterpart with equal gear. Being that Dodging is our only way to avoid taking damage and saving our healer's mana, it is a very very important stat.
On top of that, critting is how we generate massive amounts of rage, as well as increased threat(because of increased crit damage - see the talent Predetory Instincts for increased Critacal Hit Damage). With a high enough crit rate, you can sustain your threat on your damaging hits alone, and not have to rely on being hit (like Warriors and Paladins do). To break it down, More Agility = More Crit = More Rage = More Threat. Agility is your most important stat because it gives you both mitigation as well as threat generation.
Stamina increases your hit points. In bear form you get an increased amount of stamina from both Bear Form and Heart of the Wild. The point of stamina is to survive the hits you DO take. With 50% dodge, you will still take half the hits dished out- surviving them is important.
Increases your chance to hit the target. Although this is nice, and other druids will arguably tell you to look for +hit gear, I find it an unimportant addition to your tanking gear. If you get the Earthwarden (as all Feral Druids better) you can make up for the lack of +hit with the Feral Combat Skill Rating. But really, even without it, the amount of threat we dish out on any hit what-so-ever is enough to make up for not hiting 100% of the time. Don't bother with it unless it's already on it (Sun Gilded Shoulder Pads and the Boots of Natural Grace for example).
Defense Rating and Resillience Rating
Stack enough of these to get a 2.6% reduced chance not to be crit in addition to the talent Survival of the Fittest then stop getting it. Defense rating is more expensive than Resillience, so if you can get it through resillience alone, have at it. It's unlikely, however, but if ya can feel free. We only get half the benefit of defense rating that warriors get (miss and dodge, discounting crit reduction), so why waste points?
I left out Crit Rating and Dodge rating because of the simple fact that Agility gives both of these, and we need less points of it to get the same benefit. I also left out armor because, well, you should know what it does. The only important thing to know is that armor caps out at about 37k, so don't stack beyond it. There's no point.
Now, all high end druids will agree with the uses of the stats that I've explained above. You will, however, find some druids that focus more on stamina than agility, which is still a good way of looking at it. For 5 mans, high stamina is very nice because you'll want to get hit. Why? Well, it's unlikely that you'll have salvation on your dps as you would in a raid, and also highly likely that your dps will be, well...special. You know the ones. The rogues that cheap shot right as you hit him, not allowing you a moment to get aggro or the possibility of building rage off their hits. The mages that open up with a PoM Pyro. The locks that Searing Pain(why? Who knows.). Or the Elemental Shamans that add a shock in the rotation (Zomg threat!).
In these situations, you might find that Stamina > Agility, because you'll WANT to be hit as many times as you can get out. You may even find a little hit rating useful so that if they pull aggro, you can always get it back. But generally, the progression of stats after you gain crit immunity should look like this:
Agi > Stam > Armor > Hit Rating > Strength > Dodge Rating > Crit Rating
For information on Threat, I recommend you read Druid Threat Values on the Of Teeth and Claws blog. It lists out the threat of each ability, so you can see the importance of strength and other such stats in mathmatic form! =D
On a side note, Kailora hit #1 dps on Tidewalker today about one minute before a wipe! Who says ferals can't dps? =)