Reg DS is easy too now with the buff.
That's how it is for us too. We were working on Heroic Hagara last night, and ended up swapping to normal so we could continue on Friday (an aside: ugh, I hate raiding on Fridays) with Heroic Ultraxxion. The boss felt like a slightly long trash mob fight (took about 2.5 minutes to kill).
I think our main issue on Heroic Hagara is managing the ice lance properly. If you let someone get higher than... I think 4 stacks, Hagara can one shot them with her Frost Shock-like thing. We had that happen a few times to one of our healers. We also found it
immensely easier with our Hunter so we would have Aspect of the Pack during the frost phase. With all the target switching, I prefer doing the fight as Combat on my Rogue, but I'm simply too slow without the +15% speed boost from Assassination. So having Pack made it so I could easily do the fight as Combat and not have to worry about lacking a 5x stack of Deadly Poison on the frost pillars.
Whenever we would get Hagara to about 40% or so, one of the things that tended to kill us was the fact that 2 out of 3 of our healers were chosen for the ice block. Given there are only 2 ice blocks that go out at each interval (on 10-man), that's extremely bad luck. I mean, there's a 1.3% chance that two healers will be targeted (1/9 * 1/8 -- out of 9 because the tank cannot be frozen), and we had it happen at least twice. Even the cooldowns, full-on heavy heal spam and the tank healing himself (Paladin) couldn't keep the tank up through Hagara's Assault mechanic (super fast attacks for ~5 seconds).
Oh well... maybe we'll kill Heroic Ultraxxion again on Friday. I was just glad that I finally got my shoulders off Morchok on Tuesday! Now he just needs to give me my ranged weapon and someone needs to drop that physical DPS trinket (the vial).