New buff system and class requirements

All the raids a piece of cake for most of the guilds. You can wear
blue&green to run through karazhan; you can clear Zul’Aman in 2 hours
with T4 gears.

Now New buff system and class requirements has came out:
Our goal was not to remove anything unique from the classes. Our goal
was to get rid of anything that was considered so mandatory that you
would consider scrapping a raid without that player. A great example
is Bloodlust / Heroism. Raids were absolutely stacking shamans to do a
rotation of these spells to the extent that we designed encounters
assuming that would be the case.

A slightly different example is Illidan. That encounter assumed
(because it has been changed) that you had a warrior in the raid, and
that the warrior was tanking.

On the other hand, we didn't design any encounters for LK with the
thought that "They'll use a death knight here to pull," or "The druid
will use Rebirth here," or "You have to have Spell Reflect or you'll
wipe" or "The rogues need to disarm the traps in the Suppression
Room." Now all of those spells do have their uses and will make
certain encounters easier. If those spells were of questionable or no
utility then the class distinction really starts to devolve into
damage, healing and tanking. But none of them should be mandatory. I
don't think most guilds will call the raid if they don't have a DK for
Malygos the way most guilds *did* call the raid if they didn't have a
hunter (or two) and a mage for Maulgar (pre-last patch anyway).

There are a few encounters we're keeping an eye on. Naxx 25 still has
an encounter that requires 2 priests. That is probably a safe
assumption for a raid of that size, but it's a slippery slope. If we
had required 2 Shadow priests, for example, it would probably cross
the line. (And no, we won't start implementing encounters like that
when we allow dual-specs.)

I also realize that some players (particularly those who don't play
the class in contention) will argue that Rebirth or whatever is so
powerful that raids will require a druid. Maybe there are some out
there that do. A lot of these decisions are judgment calls on our
part, and as I'm sure you all know, decisions on the part of raid
leaders, especially inexperienced ones, can sometimes be misinformed.

It’s the good chance for the players get epic gears from raids before
Wotlk.
Check: www.theapwowgold.com for more information.