Grats on your kill, OP!
I do the same for my guild on 25-man- tank phase one, dps phase two and mostly dps phase three.
What I do is pick a corruptor, mark it with a star, and build five combo points on it. The warriors buid their rage on it, rogues build CP on it, and when that first set of portals comes up, I've got a 5CP savage roar ready to go for when I get in there, the rogues have S&D up, and everything's golden. I use mangle, rake, mangle, maybe another mangle and move on while I'm working on tentacles, and I save both dash and kitty charge for the journey to the brain itself. Kitty charge puts me in a position where I can shred (the brain is weird about that- some places you can, others, you can't.), and I've still got my savage roar up long enough to get another one up on the brain. Then, trinkets, berserk, haste pot, everything, and burn.
I use the shred, rip and savage roar glyphs for this fight- the three essential feral dps glyphs. My full brain rotation is:
Keep mangle up
5-point SR
Keep a 5-point rip up
Keep rake up
Shred for CP
Use 5-point ferocious bites (I usually do two if I have berserk up, one if I don't)
Refresh rip
Run like hell to the portal and gtfo.
This is the talent build I use for the fight- a standard feral dps build with three points in thick hide instead of feral aggression
Druid Talents - World of Warcraft Talent Calculator version 3.2.2 - WoW Tools
Hope this helps to make your next kill even speedier!