Very close according to what I just read on the 'net, the late bars are close to 7, regular hours its 5.50 to 5.90. Down under in the trendy Perth city centre bars its probably around $12.
That's another issue, not helped by motoring associations that are more interested in selling holidays and insurance than worrying about their driving members.
A significant issue Phil is the type of conversation. When phone legislation was first mooted it raised a number of issues including the use of two-way radio. Radio exchanges tend to be brief and mainly an exchange of information e.g. an ATC instruction. Phones tend to be used for longer exchanges and often involve some degree of thought.
Some transport companies even prohibit the use of hands free in their vehicles when in motion due to the increased distraction value.
The reality is that there are many actions, if determined to be affecting your attention to driving, that could lead to prosecution. Passing specific legislation on phones was intended to simplify things for both the public and the plods.