Cell phone driving bans becoming more common as evidence piles up

According to a Toronto Star editorial (quoted in a recent KCStar article):
[C]lose to 50 countries already have laws that ban cell phone use by drivers to some degree, including Australia, Britain, France, Germany, the Netherlands, Sweden and Switzerland. In some jurisdictions, drivers involved in accidents while on the phone can also lose their car insurance.

A study by the California Highway Patrol found cell phones have been the most common cause of distracted-driving accidents in every year since 2001.

The evidence seems indisputable. People who talk on a cell phone while driving are more likely to be involved in accidents than drivers who don’t.
There is more data about this problem here.