In reply to planetmarshall:
> ...using Siri, texting or anything that isn't driving is pretty bad form, IMHO.
I think it largely depends on context, driving 20 mins on the way to work on A roads is different to driving 5 hours on the motorway. Having music, news radio, water, cigarettes, coffee, a sandwich to munch on etc. keep you sane. I don't see them as being particularly distracting. I think it's a fallacy that you can maintain the maximum level of concentration on the road for that length of time, at least without stopping every 20-30 minutes. There's always going to be a time when you're not focused, whether you have distractions or not it's just a case of how distracting that thing is. For example, making a sandwich is probably overkill, unwrapping a sweet despite taking two hands I don't have a problem with, nor drinking a coffee.
And while were on the subject of passengers, talking to a passenger is way more distracting than taking a quick phone call.