Diana's a really great champion. I played her on the PBE server. I found her to be well rendered, well balanced, none too difficult to work with, and intensely fun, what with chasing retreating champs across the map and scoring fast, efficient kills.
Moreover, I like her personality. She is well thought out, precise, intense, focused, sharp, and strangely endearing, with her jokes and her "introverted intensity." You really get the feeling that there's more underneath the surface of her calm exterior. That there's deep, volatile emotion within her expressed in laser-focused action.
Diana's going to be an instabuy for me on my account on the Live NA server, and even more important, she's my favorite. Thank you to all who had a hand in her creation. Embrace the Rising Moon.