Some ideas as to what I might ask:

  Tell us about yourself.

  Tell us about how you work.

  How did you get started?

  What are your biggest challenges?

  What do you think of (some current trend)?
  
  What is your setup?  (hardware, software, workspace, etc.)

  What are your favorite apps?

  Any advice for beginners?

Also, who would you like me to interview? I'm thinking of a healthy mixture of experts from different platforms, ISVs and contractors alike.

Much obliged for your input!