http://raidbots.com/dpsbot/Overall/25N/#3vs00
That is overall for melee only. Of course, with ranged factored in the disparity is even more stark.
Combat is really in bad shape, falling behind feral and ret pallys -- assasination is barely edging out ret pallys.
I keep hearing on this forum, rogues are fine - l2p, but the numbers since 4.1 are telling a different story. I can only imagine that without those cleave gimmicky fights for combat to pad its numbers, combat would be in even worse shape. Of course, SUB is dead last.
But unless they change some rogue mechanics, I don't see firelands being any different.