All these opinions mean nothing, since they do not know your entire rosters, current standings, etc.
However, my worthless opinion is I like this trade.
Delgado is not guaranteed to have a good second 1/2, Alou is playing great, but he is still 38.
Zambrano is 23 and only getting stronger, Overbay is in a breakout year on a breakout club.
Perhaps Moyer/Escobar can be a wash.
imho.