Honestly? I think Citricos is a ton better.
Narcoossee's constantly has trouble with their steaks (last time I was there, a waiter reported to the chef that three different customers had complained about their steaks that night, and the chef berated the waiter and said the customers had no idea what they were talking about- owch (though we probably weren't meant to hear that)). As for their shellfish, it's incredibly overpriced: their 40$ lobster is around the quality of a 19$ lobster I can get near home (which is not exactly next to the shore). While watching Wishes from Narcosee's indeed incredible (and if you've never done it, at least head to the docks and see it), it can also mean if you're at a window table people crowding around your table to see it... or people standing outside right in front of your window so you have a lovely view of their behind. I also find their tables are as close together as Le Cellier or San Angel, without the darkness to hide it. Everytime I eat there, I feel crowded.
I think Citrico's menu is more adventurous, and the servers and chef (when we've spoken to 'em) more friendly. I also don't feel as crowded, and find the brighter atmosphere nicer then Narcosee's which feels more like 'California Grill cafeteria style, without the cool vases and awesome view and even more crowded'.
But as you can see, I seem to be a minority here.
...If you are going to Narcoossee, though, I would suggest skipping both the steak and the lobster. I've had a shrimp dish that was quite nice there; my mother once had a vegetarian ravioli that was actually delicious. The steak is almost always overcooked and the chef is not very happy about redoing it if necessary, and despite how cheap lobsters are in Floridia at the moment (at least, lobsters from the Gulf), the quality is just going down while the price is going up on them. Avoid those, though, and you'll likely be very happy.