There were two major things that happened in patch 3.0.2, the infamous patch immediately before Wrath.
First, the boss HP and overall damage was nerfed a bit. As Rmschoir pointed out, this was so the new game mechanics wouldn't stop guilds from progressing. Blizzard couldn't be 100% sure that the massive class changes that came with Wrath wouldn't make things impossible for BC styled fights. So in order to correct this, the HP nerf came.
Secondly, the boss fights were made easier because the talent trees and abilities became so much more powerful and well tuned to their individual role. Take prot warriors -- prior to patch 3.0.2, AoE tanking was more of a learned skill than a given right. You had to spend your time learning to tab Sunder like a mad man, and had to integrate Cleave into your tanking rotation. After patch 3.0.2 was applied prot warriors had innate AoE abilities, making AoE tanking easy as sin (at least compared to what it once was).
What Blizzard didn't predict, however, was that the abilities would make everyone so over powered for the time between 3.0.2 and Wrath's release, that the HP nerf on the bosses were unnecessary. Guilds who previously had no business being in even Black Temple were suddenly sporting dual glaives and making their way to Kil'Jaden in the Sunwell. Many people consider this double-nerf of the content to be too much, and a rather pointed example of how it's possible to overcompensate in the area of game difficulty when introducing new abilities.
Will Blizzard make the same mistake again?
I don't think so.
There will likely be a small HP nerf, and certainly new abilities, but I wouldn't expect the facerolling that happened at the end BC raiding to happen in Wrath.
"Why are there no female iron dwarves? Oh sure, vrykul and mechagnomes, but no iron dwarves?"
Qot answered it best: "With dwarves, just because they're bearded doesn't mean they're male." But then Ametrine came in with the correct answer: "Both the Earthen and the Iron Dwarves are constructs, not living creatures. No flesh, no gender, no women."
I love it when you guys write The Queue for me!
SG HighCharity asked....
"I've been doing some thinking. Will Deathwing's return have any effect on the landscape in Northrend?"
At BlizzCon 2009 Blizzard said they won't be changing the landscape of Northrend. So I wouldn't expect it.
"There was recently a mobile authenticator app added to the android market place, is it real?"
We believe it is. We've had reports of people having success using it, and have contacted Blizzard for confirmation. Keep an eye out on the post for more information.
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