The Enigma Order

Tanking gear _primally_ consist of
Sta
defense
armor
hit

Dmg gear consist of
Str
Agi
crit
hit

why is this information important?
Most ferals however, have a thin line between the different sets (pieces with high sta, armor and strenght etc) and it all pretty much sums down to the fact that bearform gives you some bonuses and catform others. This meens that you can have a pretty nice hybrid tank/dps set, depending on what form you are in.

but to answer your question short.. it depends on gear...
malorne feral set is nice for both tanking and dps, if you get the right trinkets and rings + gems/enchants to back it up.

I've obviously not tanked a raid encounter yet, but from what I've read, and from what I know mechanics-wise, strength is valuable as it increases your threat generation with white attacks and mauls. In a raid situation though it's subordinate to the stats mojo listed though - agility is generally considered superior to strength since it increases your crit, dodge and armor, all more important stats all in all. For 5-mans though, strength is more important than in a raid scenario since feral tanks actually have the potential to bring a fair amount of damage to the table, and every point of strength contributes to that end.