I'm a bit puzzled. Real or not, it seems peculiar to me that this guy and all the guys on Snopes are holding the snakes on a stick away from their bodies. I mean, the thing is supposedly dead, right? You just killed something that big and wicked-looking that could have killed you first, wouldn't you want to pick it up with your bare hands, hold it over your head, and pronounce "LOOK AT WHAT I JUST GOT FOR DINNER!" Wouldn't you have a big-old sh*t-eatin' grin on your face - got 'im before he got me?
That aside, the light seems a bit off on this particular pic. If you look at his hat, his shoulders, and the top of his arm which is mostly hidden by the snake, you see some real hot bright spots. But where are the hot spots in the rest of the pic? The direction of the light does seem to be hitting him from mostly overhead, but somewhat to the left - why aren't there corresponding hot spots reflecting back from the flared edges of the snake's head, for example? No hot spots reflecting off the leaves of the plants in the background, either. Now light can be a funny thing with the way it bounces around, and it could be that the hot spots are coming from breaks in the leaves of trees around him. Still, I would expect that with even that there would be other signs of brighter light in other areas of the pic, and I don't really see any. So I'm on the fence with this one - could be a totally real pic with the light just doing odd things, but could be a PS job. Could simply be the computer calc resampling to resize the pic to make it smaller managed to eliminate some of the bright spots.
Perspective alone could definitely explain the appearance of the size of the snake relative to the size of the guy - a simple change of f-stop on your camera will easily do that - anyone in a Photo 101 class should know that.