Seems that even now, several weeks into patch 4.2, DMF trinkets are still selling.
I thought the market was going to drop out. I haven't checked but there are supposedly better trinkets available within Firelands.
I suppose it will take a while for them to become a common drop so people will still want to buy the DMF trinkets.
Did I mention that firelands trash run I went on? Where the dps trinket (maybe!) "Apparatus of Khaz'goroth" dropped and I won it? Did I equip it? I was tempted, but instead ...
Oh yes, those low level DM card hand in shoulders are still selling too!