Apparently, there was one more like on the same photo. Now what I see is :
A downward pointing thumb, with '2' next to it. I thought '2 people disliked' the photo!
Suggestion: Keep showing the thumbs-up, instead of thumb down. Use a difference color to indicate that the user has 'liked' the photo. Couldn't come up with any better suggestion; but the thumb thingy isn't giving me the right impression.