The problem with picking up another WR is that he's just going to hit the bench when Crabby comes back. Unfortunately, I think the WR coprs will be Boldin, Crabby & Mannigham when the playoffs roll around. If the latter two make amazing recoveries and get back to where they were last season, they can take the "unfortunately" off of that sentence.
Baldwin MIGHT be able to pass Manningham, but I wouldn't hold my breath on that one.
Now if they can trade for a legit' #1 guy like Dez Bryant or something, that would be different.