Just in time for everyone's raiding tonight, Lead Encounter Designer Daelo has announced two important hotfixes that have gone live.
Sapphiron and Malygos both should now be working as intended.
Sapphiron's Frost aura has been hotfixed to return to levels that we've all seen previous to patch 3.0.8. This means there should be 1200 damage every 2 seconds in the 10-man version, and 1600 damage every 2 seconds in the 25-man version. Note however that the tooltip is incorrect, in that it says the damage occurs every second. According to Daelo this will be fixed in the next client patch (and no, there is no indication of when that is).
As for Malygos...