I was googling around to find out some varieties of fish that I had recently at a sushi restaurant and I came upon this site. It's pretty dizzying the variety of fish expert sushi masters need to be familiar with. I remember reading on these boards and elsewhere that some people's impression is that sushi chefs just cut up fish, and that might be the case in some sushi places, but looking at this page, it might be better to think of them more like fish sommeliers with the added ability to prepare and cook the fish. Poking around the site some more, there's some great photo galleries, most notably the Sushi Koo gallery #7 (I believe: decorative sushi). Here's a sample below. This site has also got me interested in Sushi Koo in Shizuoka, where I have a few relatives. Might be worth checking out.