I took this last year at Districts with my 50mm 1.8 AI lens. I love that with the cropped sensor 50mm lenses actually give you a 75mm focal length (compared to film/FX-DSLRs). Yesterday I spent about an hour debating in my head between the 35mm 1.8G AF-S DX and the 50mm 1.8G AF-S. On the one hand, 35mm would be easy when I am coaching. I would allow me to stand fairly close to the pool and still shoot a wide angle, but it would make it a little more difficult at meets, where I am further away. The 50mm is harder for coaching practices, but over all I think it was a better choice!
It's predecessors have always gotten great reviews, and I quite like the one that I have for my manual film camera, but it's tough to use with my DSLR, as I really enjoy metering and auto focus! I'm also so happy I waited until the 1.8 AF-S to come out this year. I almost jumped and purchased the AF, that won't auto-focus with my D5000. Anyway, I'm super excited!