The key features already exist:
Hands-free/auto answering is set on the phone (may not desirable?
Especially with other people in the car?). With the Merc integrated car kit
one can also answer by hitting a button on the steering wheel.
Calling by speaking is set on the phone, at least on some models.
I am sure Bluetooth will make things easier and, perhaps, reduce one's
dependence on expensive manufacturer's kits that tie one to particular phone
models, but will one get displays of the SIM card memory on the dashboard?
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