Interesting. Having worked with aquaculture in the past, this would likely be a very effective means to produce a large amount of food within a short time. However, GM foods scare the shit out of me and I would not touch this fish with a stick. Hopefully this particular fish is sterile, not allowing it to transfer its genes to future generations, which would likely cause further genetic mutations within the populations. I hope it's never released out of captivity. This fish is likely far more susceptible to food limitations than its unmodified counterparts. I would like to know what would happen to this fish under eutrophication, metabolic disruption and food limitation, as most fish have predictable responses to such circumstances.
I honestly don't know how to react toward GM fish. There are many unknowns that go along with GM foods, especially in multicellular organisms. I would not venture to eat this GM fish until it undergoes some very rigorous lab testing on toxicity/carcinogenicity. Even then, it's scarey shit.
I wonder if Monsanto will try to buy this shit up, if they haven't already.