Has congestion road pricing's time come?

From the AP (via ENN):

Drivers waste nearly an entire work week each year sitting in traffic on the way to and from their jobs, according to a national study released Tuesday.

The nation's drivers languished in traffic delays for a total of 4.2 billion hours in 2005, up from 4 billion the year before, according to the Texas Traffic Institute's urban mobility report. That's about 38 hours per driver.

Urban planners spend significant amounts of time and money trying to find ways to reduce congestion.  But my economic supersenses tell me that the solution is much easier. 

...The study offers a menu of options for addressing congestion, including adding roads or lanes where needed, improving public transportation and changing driving patterns through flexible work schedules, telecommuting and carpooling.

Instead of trying to find ways to spend tax revenues on more roads, why not figure out why drivers are willing to sit in traffic.  The simplest answer is that drivers don't perceive the cost they are imposing on others-in the form of longer commute times for everyone-when they commute. 

Think of it this way.  A driver sitting in traffic is willing to accept the cost of sitting in traffic-increased commute time.  But, by entering the roadway at peak hours, the driver imposes an additional cost on everyone else, by adding to their commute time.  That's a standard negative externality and we all know the simplest solution to negative consumption externalities: Get the price right. 

The price of driving during congested times is inefficiently low-it fails to capture the additional congestion cost.  So how do we get the price right?  Congestion road pricing--that is, tolls.  Force drivers to pay higher prices for driving during congested hours.  If you commute at 5:00 AM, your toll would be lower than someone choosing to commute at 7:30 AM.  By raising the price at 7:30, you give some people the incentive to shift from 7:30 to 5:00. 

Now that scanners make it much less of a burden to pay tolls--toll booths no longer add to congestion--a system congestion pricing would be relatively easy to implement: Much easier than building enough roads to try to stay ahead of the traffic.  Oh, and cities get the added bonus of increased toll revenue to fix things like bridges and roads that are worn out from handling more cars than they are designed. 

Seems too obvious.