I think the drops were due to a variety of things. I remember seeing a couple short throws to running backs that seemed to have too much zip on them. Alex could work on those touch passes... the short dump-offs to RBs and TEs. However, you allow the defense a better chance to make a play on the ball with those kinds of throws. So there is a trade-off.
Bruce Miller's bobble bothered me. But he is a converted DE so I have some patience there. Also, Manningham missed a very catchable ball. But he did have to reach for it... Overall he has played well, I'll give him a break this week.
The only player that really concerns me is D. Walker. He struggled last week and again this week. He is an experienced pass catching TE and these are easy catches that are bouncing off his hands, chest, and face. There is no excuse for that!