First, I should probably provide a disclaimer: I am a complete sucker for Milla Jovovich movies. I will watch anything that she is in and I will probably enjoy it to some degree. I don't know why I like her so much, but it probably has something to do with her tendency to play really strong female characters.
This "face-blindness" made for some really interesting filmmaking opportunities. Basically, they constantly replaced people in the film with different actors wearing the same clothes to represent what Anna sees and feels. Unfortunately, this made it really difficult to follow characters at times. Although it's possible that this was the filmmaker's intent, I think it would have been better to make it a little easier to identify some of the characters.
Aside from the character recognition problems, my only other complaint is the fact that Milla Jovovich wasn't playing her usual gung-ho female character. That's not really a valid complaint about the film though. Faces in the Crowd is a fun, albeit flawed, psychological thriller. It's worth checking out if you're a Milla Jovovich fan, but not essential viewing for the average moviegoer. 6/10