Someone posted this in my guild forums:
Simulationcraft for 4.1.0 (Live) for a Patchwerk fight in full 372 gear: http://www.simulationcraft.org/410/Raid_T11_372.html
Now for Simulationcraft for 4.2.0 (PTR) for the same Patchwerk fight in full 372 gear http://simulationcraft.org/420/Raid_T11_372.html
Our arcane mage tends to beat my arse most of the time, but not always by much, and sometimes I beat him, yay rng. He's glad to have competition from a fire mage, though, because he didn't before he came to our guild.
I'm sticking with fire until I can't get by with it anymore, because the whole idea of arcane @#%^s with my head as it is right now. But our resident arcane mage has made a nice tutorial post for me for when/if I'm ready. I like having frost as my OS for dailies/farming. Anyway, the best part of his post mentions an addon that will reforge your gear in one fell swoop, sort of like an outfitter type thing. http://wow.curse.com/downloads/wow-addons/details/reforgesaver.aspx
Makes it a LOT easier to switch specs from one boss to another.