I've seen those pictures in the Fortean Times. The more I've seen them here and there, the sadder, not evil, I think they look. Mind you, I did feel sorry for Hannibal Hector in Silence Of The Lambs, as I felt he was a greatly misunderstood individual, and I sobbed so hard when the shark in Jaws, and it's sequels, got killed, as it was only following it's instincts, so maybe my opinions are a little weird, but I really do think the faces are sad, and not at all evil in the slightest.
People communicate expressions and feelings through faces, that's why someone started the whole smilie faces thing, so it is possible to fomualte faces out of anything, and with the emotions involved with the 9-11 day, we are finding a lot of coincidences, and images in things that don't normally attract our attention.
It's a bit like reading the horoscopes in the newspaper. Cut them out without their identifying signs, and you can make virtually all of them apply to yourself. We as humans are constantly asking questions, and we often also look for a higher power to answer those questions too. Maybe this image is just our way of looking for another unanswerable question.
If you fold a US $20 bill in certain ways, it can produce the image of the Twin Towers burning, the Pentagon Burning, and the word Osama. The 9-11 incident, is a tragdey we will always be asking why it happened, and searching for answers and clues.
Peace, Love, and Happiness, Always