A possible explanation of how they do it after the jump.
Once the shock value wears off and you start to think about this logically, you realize that there's no way possible for the fish to still be alive. If it's getting deep fried, its blood would boil when they dipped it in the hot oil. The poor thing's heart would have burst immediately. It's dead.
A few folks on the Huff Po post thought it couldn't be real because the fish would have to be gutted before cooking, but I've been to a couple of Chinese restaurants that served a whole fish like this that wasn't gutted. Tastes differ from culture to culture, I guess. I don't know if fish innards are a delicacy or not, but how many cultures use fish eggs regularly? Not just Asian countries!
So how do they do it? They dip the fish in the oil while holding it's head out. By keeping the fish above the grease from the gills up, the brain and nervous system isn't destroyed. When a fish is tapped on the mouth after its died (as they do with the chopstick in the video), a reflex reaction will cause the mouth to open and the gills to flush. I've seen it happen when I'd go fishing with my dad and uncle as a kid.
Granted, they never cooked the fish before making it twitch - for which my childhood dreams are forever grateful. I have enough neuroses already without being afraid of fried fish too!