Tigole posted on the Raids & Dungeons forum last night that the Lady Vashj encounter will be receiving a hotfix some time within the next 24 hours to re-tune the encounter slightly.

> We're in the process of making a hotfix to the Lady Vashj encounter. The hotfix entails a slight adjustment to the hitpoints of some of the adds that spawn during the encounter. The fix should go live in the next 24 hours.