Mobile Phone use in cars

I was watching a young female P plater on Friday talking on her phone with her right hand against her ear whilst driving a manual car, so one hand to steer & change gears
I really had a good stare at her whilst stopped at the lights in fact did not look away for at least 1 minute.... needless to say I got the bird & same was returned so I decided to get the hell away from here ASAP as she was a menace. This whole episode + the segment on sixty minutes last night got me thinking about the use of mobiles while driving.
What I really want to know is what would be the difference between talking hands free & talking with a passenger? I constantly see female drivers with female passengers engaged in the deepest of conversations including both hands used for gesturing whilst driving & I wonder if this distraction is as dangerous as hands free mobile phone use

What I really want to know is what would be the difference between talking hands free & talking with a passenger? I constantly see female drivers with female passengers engaged in the deepest of conversations including both hands used for gesturing whilst driving & I wonder if this distraction is as dangerous as hands free mobile phone use
