I have a 46 sorc (31 Lightning tree, a little in Madness) and post-1.2 I have seen a big change. In PvP I used to be able to do ~130k+ damage in a match. Now I do ~80-90k and I'm not doing anything differently.
The biggest change I have seen is that I am dying a lot easier. I went 1v1 against another sorc in a match that was a few levels lower than me and despite throwing everything at him, he managed to dps me at double the rate or more. By the time he killed me I had done maybe 1/4 damage to his life bar.
Now I'm not one of those who gets heavy into the optimization of my build, but I'm starting to think maybe I might have to. I used to hold my own 1v1, even against Marauders and Juggs, just fine (I would lose, but I could tie them up for a time) and now I get ***** in no time flat.
PvE is fine though, to use another poster's phrase, I can sit still and nuke until my eyes bleed. I usually use Khem Val to tank and just fling Force Storm and Chain Lightning when it pops from Lightning Storm.
TL;DR: Overall still happy, but confused and dismayed at the nerfing in PvP.