We ate at Fulton's a few months ago and were pretty disappointed, especially for the price. We didn't feel like it was a good value at all.
Nothing was terrible, but nothing was outstanding. Service, food and atmosphere were all just so-so. Honestly, I thought the food wasn't much of a step above a Red Lobster or Joe's Crab Shack, except on nicer plates. We have lived in and around New Orleans all our lives, so maybe we shouldn't expect seafood restaraunts to be as good as they are at home.
Anyway, for the price we've had much better experiences at California Grill, Artist Point, Jiko, Le Cellier, and Flying Fish. IMO, any of those would be much better choices (depending on your preferences) for an upscale meal at WDW.