If it's store-bought "fresh" I can't tell much of a difference...except as you say with the defrosting time. I do prefer "fresh" though....sometimes the frozen ones seem a little drier.
However, we live on a farm & the owner raises ducks, geese & turkeys. If that's the type of fresh you're talking about, there's HUGE difference! I still actually prefer a store-bought bird, but my DH likes the farm bird better. I think it tastes slightly more like a game bird. Sorry - that's the best I can describe it.