From mmo-champion

Sapphiron - Aura bugged / not affected by Frost resist?
We've made no explicit changes to the encounter on the design side to change how the frost aura works. When Sapphiron enters combat, he casts a spell on himself that every 2 seconds casts the debuff players receive, which you see as &quot;Frost Aura&quot;. That debuff is a 5 second duration damage over time effect that deals frost damage every second. The only difference between the 10 and 25 player versions of these spells is the amount of damage.

So if you were only getting damaged every 2 seconds previously in a 10 player raid, and still are only getting damaged every 2 seconds in a 25 player raid, there's some kind of odd bug going on that I'll have to track down. Especially since the data says you should be taking damage every second. 

Once we find out what he bug is and correct the problem, we'll adjust the numbers if needed to closely match the damage that players have been experiencing when WotLK shipped. We're not trying to adjust the difficulty of this fight, but we need to determine what's happening so this bug doesn't cause problems with future encounters. 

Here's the thread it came from.

[url]http://forums.worldofwarcraft.com/thread.html?topicId=14697621780&amp;sid=1&amp;pageNo=1[/url]

So maybe we didn't become total douchers who totally forgot to play.