I'm in my last semester of university for CS (starting graduate school in the Fall), what kinds of 'pre-reqs' would you suggest in terms of languages/programming paradigms/statistics knowledge?
What is the weekly number of hours we should be prepared to commit?
If you haven't already, I would recommend taking an intro to databases course. A machine learning course would also be helpful, if you have time to take it before you finish. Other than courses, I would try to build some weekend projects that demonstrate your ability to write clean, modular code.
Regarding hours: Insight is really intense, so while the official hours during the six week program are M-F 10am-6pm, most Fellows stick around pretty late each evening. The peer-to-peer learning aspect of the program is one of its biggest strengths, and you get the most out of that when you can be around the office collaborating with others as much as possible.