Snopes responds thusly: "The interesting aspect lies not in the analysis of the image, but in why so many readers considered it plausible enough to forward to us for verification."
Interesting, indeed. There's no telling how many people will fall for a laughably bad Photoshop job.
I've actually been methodically working my way through snopes.com in the past week (instead of the usual visit strictly to debunk an e-mail) and encountered that page on Monday.
I think once I get back to feeling normal, I'm going to make it a hobby to make up composite pictures and stories, then let them loose and see how far it goes (including if it makes it to Snopes). I'd already thought of making up fake, but believable, blog entries before that.