I don't know where those high numbers in Rawr come from. I tried Frost in raiding, the rotation was followed relatively ok, there were minor mistakes (such as a deep freeze not being done before a frostfire), but even if I did the rotation perfectly, or almost, it would still barely reach an overal of 20.5k when arcane could do a 22.
It's also a bit immobile compared to what I thought. If you have no procs to use, one has to stay for seconds casting frostbolt in several occasions. That makes it feeling like arcane in those times.
It seems very reliable to follow a rotation compared to fire (combustion is hell to set it up reliably) but the overall result seems a bit weak. I suspect it may need a buf but they are trying to nerf it in pvp so it hurts pve.
I reserve some judgement in case perfecting rotation makes a leap in DPS.