R. Bill Mountain noted in the previous article about the picture. The picture is indeed of a smiling Alan Moore holding a copy of the movie Watchmen, while putting his arm around Watchmen director Zach Snyder.
It is a photoshopped picture. Moore's rants against Hollywood and how it adapts his properties are so well known they're bordering on cliche. On the plus side, if he keeps it up, soon he'll cross the line and turn into self-parody. (My favorite option).
Anyway, the pic came from this wonderful Cracked.com article entitled "The 7 Stages Of Nerdgasm". It's definitely worth a good read, and is frighteningly accurate.
For what it's worth, I really can't wait to see this movie. I really hope it deserves multiple viewings. Because I'm going to see it a lot.