Of course, it's terrible. And I hate to think of what they construe TSOG to be (You are literally waging war on the servants of god). If you read the confession, or listen to it, whatever (I think it was originally televised, so I'm sure you could find it), it is obviously nonsense. You can find a link to it in the article.
At face value the idea of a games developer being a CIA agent seems ridiculous. And I don't believe it. But then you throw in the fact that he has made games that 'oppose' Iran, and he has had a military and espionage based background, and, well, I still think its nonsense, but I wouldn't blame someone for thinking it plausable. The thing that swings me utterly toward it being false is the confession. Obviously, forced confessions aren't hard to produce, and some of the things said; the fact that it seems that he knows the reason behind various US moves - and that they all apparently have an evil ulterior motive - leads me to believe that most, if not all of it is untrue (After all, why would you tell an agent the exact reason behind every operation? Did they send him out of the briefing with a slap on the back and a 'Be sure to tell the Iranian Intelligence Service all this stuff if you're captured?' Insanity), created by the Iranian Intelligence Service and vocalised under duress.
Still, a man's life is in danger here, so I'm going to take the stance that either way, he doesn't deserve execution, and I hope he gains whatever reprieve the Iranian court uses.