In the Wild West that is online video, Hulu.com has proven to be a trailblazing answer to how professional content can thrive on the Web. It’s this year’s pick for Web site of the year. “This is period of great experimentation in regard to media, in regard to online video,” said Hulu chief executive officer Jason Kilar in a recent interview. “You’ve seen a lot, you’re probably going to see even more in terms of various business models, various interface designs. I personally love to operate in moments of time like that.”