http://www.worldofwarcraft.com/patchnot ... notes.html

One big change in the patch is mounts at level 30.
Most of us are already level 70 though, so that may not be as interesting.

Of more interest to Mages, Warlocks and Shadow Priests is that Curse of Elements and Curse of Shadows are going to be combined.
That means, if you only have one 'lock in the raid, we'll no longer be fighting over who gets the 13% damage boost, we can all have it ^_^;;
If there is more than one two 'lock, in the raid then it's going to mean one more curse available too.