Oh there's definitely a taste difference - mainly because of diet. Farm-raised salmon eat feed made of various grain-starches, oils, and fish meal supplemented by vitamins and minerals whilesalmon in the wild eat a much fifferent diet. But nutritionally there isn't a substantial difference.

As an aside, the salmon fisheries in North America are some of the best-managed and most sustainable in the world. So if you can afford it, then wild caught salmon is a great choice.