Spitfire that is reassuring.  I too am more inclined to engage in general chat rather than get personal - it's just my way.  

I would say I am as friendly with any boss I have worked for as much I am with co-workers.  I always find if my boss doesn't divulge information that is his/her way of telling me they want to keep it that way.  

Getting to know your boss in a professional capacity is a different thing entirely from getting to know someone on a personal level.  I don't think you can ever get to know someone professionally and personally unless that individual opens the doors for you to do so.