Well, like the title says, I am looking for some help reforging. Just hit ilvl 536, got my meta, and whatnot. I currently run demo ms/affli os (I know, but demo is my love). I don't really know what I should prioritize to keep both specs happy with my gear.
Askmrrobot says Crit>Haste>=Mastery for Demo, which is reasonable, but you can probably get away with some crit and the rest into haste.
For Affliction, you'll be better off Mastery stacking since there's a lot of multi-target fights on Siege and get a soft-cap of Haste, up to 9700 or 10500, whichever you see fit. Haste is a very good stat for Affliction, so you won't be losing a lot.