Metro Replacing Station Speakers and Monitors

I got a question during this week's Live Online and said I'd ask Metro about it.

The question went like this:
Alexandria, Va.: Traveling through the Pentagon City Metro station yesterday, I noticed a series of what appear to be speaker boxes being installed at regular (10 foot) intervals along the platform. Are these part of Metro's efforts to improve communications?
Will they be installed throughout the system? And most importantly, will they help to create sounds and announcements that are not only audible, but also INTELLIGIBLE?

Candace Smith, a spokeswoman for Metro, said the work at Pentagon City Station is part of an $18.8 million program the transit authority announced in June 2005 to replaced the aging public address systems and closed circuit television monitors in the underground stations. It's a three-year project.