I will throw out a quick, brief few points of my own, short-hand guidance, but, for the real dish you'll want:
So, on gearing as a bear:
I prefer to stack stamina and agility primarily. Blue sockets get pure stam, red get Agi/Stam, many enchants get Agility or Stamina. I'm a sucker for socket bonuses so I will use Hit/Stam if I need to match a yellow socket and am not hit capped, Crit/Stam if I am hit capped.
The distinction is that bears get great Stam scaling from talents/form so Stamina will feed you loads of health. Agility scales fairly well from talents, and will give you nice amounts of dodge, armor, and crit, all of which are survival tools, and dodge and crit will feed your threat a fair bit too. The armor will help your stamina scale even better in terms of effective health.
For rotations, it will take time to find the right pacing, but in the guide linked above you can watch as he uses his skills smartly. Generally speaking Mangle and Feral Faerie Fire are your two hot threat spikes, but they have CDs. Ideally you'll want to use them as soon as they're available. Lacerate stacks support longer duration threat, and Swipe+Glyphed Maul becomes laughable group threat (I've tanked entire 5-mans using nothing else just to see if I could, it worked).
Read the guide. The Darksend is good.