Last night, Blizzard made two hotfixes to Druid abilities, as they felt that the overall performance of said abilities was sub-par for tanking Druids after the changes in 2.0.10.

Hotfix 3/06/07

• The Druid ability Lacerate will now land a small amount of instant damage, causing it to generate threat against bleed-immune creatures.
• The Druid ability Mangle (Bear) will now generate 50% bonus threat.

Additional explanation for these fixes and information on Armor:

We’ve taken a close look at constructive feedback provided on our Druid Bear changes, and are hotfixing the following changes today:

1. Lacerate will now do a small amount of direct damage to the target. This means it will generate threat rather than an immune message when used on bleed-immune creatures. However, bleed-immune creatures will still not receive the debuff from Lacerate. This should address concerns about Druids being able to tank in specific bleed-immune encounters. 2. Mangle (Bear) now generates 50% bonus threat on its damage. We realized that in reducing Mangle damage, we made it less useful as a snap aggro tool. This threat bonus moves it back up to almost where it was before the 2.0.10 changes.

In addition, we examined concerns about the best Feral Druid armor pieces being outdoor world quest rewards, and Druids feeling their tanking ability would not scale with better gear. We are adjusting superior and epic leather pieces designed to be used by Bear Druids and increasing the armor on many of those items, particularly raid sets. These changes, however, will not show up until patch 2.1.0.

Source: http://forums.worldofwarcraft.com/thread.html?topicId=79628116&sid=1