Telling someone to blindly stack stam is bad advice.
Telling someone to blindly stack agility is not so good advice.
Aside from getting enough stam to avoid being gibbed, what may work for the random's in this thread may not work for your raid composition.
Agility is still a druid tanks best stat, this has never changed & there is no arguing this. All expansion it's always been best to get enough stam to tank the content your tanking and/or what your healers feel comfortable with. This EH threshold may be different from druid tank to druid tank, raid to raid, but that's something you gotta use your brain for and look at whats hitting you and TALKING WITH YOUR HEALERS. <-- most important part imo.
http://theincbear.com/ best source for bear tanking imo
This is a recording. BEEP.