Lol well after Combustion nerf AND CM nerf (well... nerf then buff 1.25 to 1.3) I really don't see them being able to change much other than spell co-efficients and/or adding pyro back into combustions equation. Both of which I give basically a zero chance of happening.
Again though, looks as though fire is going to scale amazingly well as well as we get quite a few cleave fights in this next tier from the raiding videos I've seen from PTR.
I think as we come close to approaching 35-40% raid buffed crit fire is going to laugh at other mage specs as we always do toward the latter end of an xpac. I just think we are going to get to shine a bit earlier this time. RIP arcane, I will not miss you.
(This is not a comment on if Arcane is viable, just my massive distaste for the spec
)