Haven't been on in a while, so my two cents on his last few weeks:
Parrying - I don't recall this being a problem last season. Off the top of my head i remember the double save at home against Arsenal where he parried Arshavin's shot, away at Spurs the deflected shot that Evans was alert to and cleared and Athletic where he was moving backwards into position got a hand on it and Muniain got there first.
If anything, maybe it's the timing of the dive. What he is doing now gets a full, strong hand on it. At full stretch, fingertips would see it past the post. Maybe going down with two hands can get more distance on the parry. All things he was doing last season.
On yesterdays game - Excellent and i thought we might see a shutout. Thought the second save might have come off his hand actually, just the way it bounced away. The communication between him and Vidic was bad again for the goal. Vidic was desperate to get in Caulkers way, but was not clearing that. In the end he ran into de Gea again and probably made the punch more difficult. Thought if he stood out the way and blocked Caulker a bit, de Gea would have gotten it away from Lennon atleast. I can understand the scramble at that stage of the game though. He is definitely better in the air this season, as he proved away at Villa, but the consistency is not there yet.