I am legend

Were the infected people getting smarter? Were they the ones that moved "Fred" and set the trap or was it Anna that did that?

1. Not enough backstory.

2. A lot of lost potential with the infected. The part when Neville got trapped by the rope was both the best part of the movie and also where the movie really started going downhill for me. You see that the infected are intelligent enough to re-create Neville's trap (and it seemed to be implied that the 'leader' of the infected was after Neville because he kidnapped the female infected), and yet none of that was explored.

3. The scenes where Neville was losing his mind felt out of place because he always went back to normal in the next scene.

Sam was awesome and went down protecting her master. Sad though that she died. At least the last moments of her life were good ones, If you don't count the fact that he had to put her down with his own hands.

The ending where the cure is taken to the "Safe" Colony is just a let down for me, and when Neville gives his life for the people to start anew, I just think that they could have done that a different way.

Neville in the novel was killing the vampire creatures when they were sleeping during the day time because they reverted to a more docile state. The new society of creatures became terrified of this monster, Neville, who would come into their homes and kill them cold bloodedly.

Neville was doing it out of hatred and fear for the creatures and thinking only of himself, without really realizing that they have formed their own society. In the end he is caught by hunters of the society for his crimes and given the chose of suicide or execution. Neville chooses suicide because he realizes he was the monster all along and that he became The Legend that the vampires feared, just as humans feared the legends of vampires in the past.

So he realized he was the legend due to his crimes, not because he was the only human left.