Couple things I would recommend is getting some more Cata gear come 5.1 (I know I can't wait for it for my last 2 pieces), If you aren't running with a healer and playing fire my opinion of mage is we are a bit squishy so I'd suggest going for more resil and of course more PvP Power with Cata gear. I would look at getting the Repression Belt if you can find one, I know it was a pain for me to get my second one for PvE, and as hypocritical as I sound saying the professions should be higher to be optimal, I also recommend alchemy for the trinket. I personally like the legendary (I'm not sure if it would be possible to get). Apart from those things it looks good to me.