Tai. Probably the best neta (topping) you can have for sushi. Served w/ momiji-oroshi (grated daikon w/ srirach, or chilies), negi and a dash (not shower) of ponzu. It's meaty, slightly chewy, soft, and ever so succulent. The meat is slightly sweet and is very easily over-powered (hence the "dash" of ponzu).
A truly wonderful fish, it saddens me though, that so many sushi-ya try to pass izumi-dai off as tai. Izumi-dai, or tilapia, is typically, if not always, bought frozen, then defrosted before service. It's meat is much firmer and more opaque (almost white) than tai is. As far as taste goes, I can't say. This is because the places that usually serve this "fake" snapper, OD the fish with so much sriracha and ponzu that the fish itself becomes indistinguishable.
I suppose, a good rule of thumb to follow for spotting tilapia is to check the happy hour menu.
If they have 'snapper' on it, then it's probably izumi-dai.
Why though?
Simply because real snapper is just too expensive to discount. Has anyone here ever seen ootoro up for happy hour?