I am very observer

I just got this thing in my e-mail. It has these very cool optical illusion artworks in it. Some I've seen before, and some new ones. The one that really cracked me up though had this great caption. It says:

"There are 11 human faces in the picture. Can you find them all?
Normal people find 4 or 5 of them.
If you find 8 of them, you have a extraordinary sense of observation.
If you find 9 of them, you have a sense of observation above the average.
If you find 10 of them, you are very observer.
If you find 11 of them, you are extremely observer."

I really wanted to be extremely observer, but got distracted wondering how someone who put so much effort into putting together all these cool visual effects could fail to see such obvious butchery in the caption.